.\" -*- nroff -*-
.\" =========================================================================
.\"
.\" @(#) draft-bidulock-sigtran-loadgrp-00.me,v 0.8 2002/04/02 08:10:54 brian Exp
.\"
.\" -------------------------------------------------------------------------
.\"
.\" Copyright (C) 2002  OpenSS7 Corporation <http://www.openss7.com>
.\"
.\" All Rights Reserved.
.\"
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of this
.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
.\" permission notice identical to this one
.\"
.\" Since the Linux kernel and libraries are constantly changing, this
.\" manual page may be incorrect or out-of-date.  The author(s) assume no
.\" responsibility for errors or omissions, or for damages resulting from
.\" the use of the information contained herein.  The author(s) may not have
.\" taken the same level of care in the production of this manual, which is
.\" licensed free of charge, as they might when working professionally.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by the
.\" source, must acknowledge the copyright and authors of this work.
.\"
.\" -------------------------------------------------------------------------
.\"
.\" U.S. GOVERNMENT RESTRICTED RIGHTS.  If you are licensing this Software on
.\" behalf of the U.S. Government ("Government"), the following provisions
.\" apply to you.  If the Software is supplied by the Department of Defense
.\" ("DoD"), it is classified as "Commercial Computer Software" under
.\" paragraph 252.227-7014 of the DoD Supplement to the Federal Acquisition
.\" Regulations ("DFARS") (or any successor regulations) and the Government
.\" is acquiring only the license rights granted herein (the license rights
.\" customarily provided to non-Government users).  If the Software is
.\" supplied to any unit or agency of the Government other than DoD, it is
.\" classified as "Restricted Computer Software" and the Government's rights
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.\" FAR (or any successor regulations).
.\"
.\" -------------------------------------------------------------------------
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.\" SS7preBetaRelease(0.8) modified 2002/04/02 08:10:54 by brian
.\"
.\" =========================================================================
.R1
abbreviate A
label L
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join-authors ", " ", " " and "
et-al " et al" 2 3
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# sort A+
# reverse A
.R2
.de $0
.if \\$3>0 \{\
.if \\$3<4 \{\
.(x 0
.ie '\\$2'' \\$1
.el \\$2 \\$1
.\"'
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.fo 'B. Bidulock'Version 0.0'FORMFEED[Page %]'
.ds |x txt
.ds #n <\\**>
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.ds &f Figure\ 
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.(x 2
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..
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.de #e
.if \\n($d>1 \{\
.uh "Endnotes for Section \\\\n($1"
.pd
.\}
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.ds a \a
.bp
.he 'Internet Draft'UA Load Grouping'January 10, 2002'
.TS
expand tab(;);
l c r.
Network Working Group;;Brian Bidulock
INTERNET-DRAFT;;OpenSS7 Corporation
.bl 2
Expires in six months;;January 10, 2002
.bl 2
.TE
.(l C
\fB\
Load Grouping Extension
for
Signalling User Adaptation Layers
<draft-bidulock-sigtran-loadgrp-00.\*(|x>

.)l
.rr |x
.ne 4
.uh "Status of this Memo"
.lp
This document is an Internet-Draft and is in full conformance with all
provisions of Section 10 or RFC 2026.  Internet-Drafts are working documents
of the Inetnet Engineering Task Force (IETF), its areas, and its working
groups.  Note that other groups may also distribute working documents as
Internet-Drafts.
.lp
Internet-Drafts are draft documents valid for a maximum of six months and may
be updated, replaced, or obsoleted by other documents at any time.  It is
inappropriate to use Internet-Drafts as reference material or to cite them
other than as 'work in progress'.
.lp
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
.lp
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
.lp
To learn the current status of any Internet-Draft, please check the
'1id-abstracts.txt' listing contained in the Internet-Drafts Shadow
Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe), munnari.oz.au
(Pacific Rim), ftp.ietf.org (US East Coast), or ftp.isi.edu (US West Coast).
.uh "Abstract"
.lp
This Internet-Draft describes an extension parameter and procedure to the
Signalling User Adaptation Protocols,
.[
RFC 3057
.]
.[
dua-00
.]
.[
v5ua-01
.]
.[
m2ua-11
.]
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
based on the Stream Transmission Control Protocol (SCTP)
.[
sctp
.]
which permits an Application Server Processes (ASP) to indicate its placement
within a Load Group and permits an Signalling Gateway (SG) to distribute
traffic over Load Groups under Application Server Process (ASP) control.
.lp
The described procedure provides for Override, Loadshare and Broadcast traffic
mode operation within a Load Group consisting of one or more Application
Server Processes (ASPs) resulting a mixture of traffic modes within an
Application Server (AS).  The parameters and procedures described here
supplement the \fI\)UA Load Selection\fR
.[
loadsel-00
.]
extension parameters and procedures for improvide distribution of traffic over
ASPs and Signalling Gateway Processes (SGPs).
.sh 1 "Introduction"
.sh 2 "Scope"
.lp
This Internet-Draft provides the \fI\)Load Distribution\fR parameter and
associated procedures in extension to the parmeters and procedures of the
Signalling User Adaptation Layers (UAs),
.[
RFC 3057
.]
.[
dua-00
.]
.[
v5ua-01
.]
.[
m2ua-11
.]
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
and the \fI\)Load Selection\fR
.[
loadsel
.]
extension, for the purpose of permitting Application Server Process control
over grouping of ASPs into Application Servers as part of the procedures of
these UA protocols.
.lp
This \fI\)Load Grouping\fR extension is intended to be compatible with UA
implementations not supporting this extension.
.sh 2 "Terminology"
.lp
This extension supplements the terminology used in the UA documents
[IUA...TUA] and the \fI\)Load Selection\fR extension by adding the following
terms:
.lp
\fI\)Load Distribution (LD)\fR \-
.ix +\n(iiu
a \fI\)Traffic Mode Type\fR which is applicable within a \fI\)Load Group\fR.
.lp
\fI\)Load Group (LG)\fR \-
.ix +\n(iiu
a group of ASPs that share the same traffic distribution within an Application
Server.  An ASP is permitted to belong to more than one \fI\)Load Group\fR for
a given AS.
.lp
\fI\)Load Selection (LS)\fR \-
.ix +\n(iiu
an identifier that uniquely identifies a \fI\)Load Group\fR within an
Application Server.  This identifier is only guaranteed unique within the
scope of an Application Server and must be combined with a \fI\)Routing
Context\fR or (set of) \fI\)Interface Identifier(s)\fR to uniquely define a
\fI\)Load Group\fR at a Signalling Gateway.
.lp
\fI\)Signalling User Adaptation Layer (UA)\fR \-
.ix +\n(iiu
one or more of the Stream Control Transmission Protocol (SCTP)
.[
sctp
.]
Signalling User Adatapation Layers.
.[
RFC 3057
.]
.[
dua-00
.]
.[
v5ua-01
.]
.[
m2ua-11
.]
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
.sh 2 "Overview"
.lp
Existing UA procedures with regard to traffic distribution and ASP traffic
management provide a mechanism to select the algorithm for coordinating state
and distributing traffic over a number of Application Server Processes (ASPs)
serving an Application Server.  These existing procedures provide only
simplified distribution approaches which are not ammeniable to large scale
systems that need to adapt to dynamic traffic loading or need live
reconfiguration for maintenance purposes.
.lp
This extension to the Signalling User Adaptation Layers
.[
RFC 3057
.]
.[
dua-00
.]
.[
v5ua-01
.]
.[
m2ua-11
.]
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
permits close control over the grouping of Application Server Processes
serving an Application Server that provides the following capability not
existing in the current scheme:

.ip "Grouping of ASPs into Load Groups"
Under the existing approach, each Application Server Process acts
independently with respect to an Application Server.  This approach does not
provide for the grouping of ASPs into workgroups, not does it provide
coordintaed control of the role of groups of ASPs serving an ASP.  As a
result, the existing scheme does not scale well in this regard.

This extension draft provides for the grouping of ASPs into load groups with a
traffic distribution mode (Load Distribution) within the load group that is
independent of the Application Sever traffic mode.
.sh 3 "Existing Traffic Distribution"
.(z
.(c
.nf
.sz -2
\fC\
                                    ____
           Traffic                 /....\\
           Mode Type          ____|__....|
 _______                     |       |...|
|       |------------------->|  ASP  |...|
|  SGP  |-----\\              |_______|...|
|_______|----\\ \\              ____|__....|
         \\--\\ \\ \\            |       |...|
             \\ \\ \\---------->|  ASP  |...|
 _______      \\ \\            |_______|...|
|       |      \\ \\                |......| Application
|  SGP  |       \\ \\               |......| Server
|_______|        \\ \\              |......|
                  \\ \\             |......|
                   \\ \\        ____|__....|
                    \\ \\      |       |...|
                     \\ \\---->|  ASP  |...|
                      \\      |_______|...|
                       \\      ____|__....|
                        \\    |       |...|
                         \\-->|  ASP  |...|
                             |_______|...|
                                  |......|
                                   \\____/
.sz +2
.)c
.#f "Existing Traffic Distribution"
.)z
.lp
\fI\*(&f\n(&p\fR illustrates the existing traffic distribution algorithm that
is used across the Signalling User Adaptation Layers.
.lp
When an SGP distributes a Signalling User Adaptation Layer message towards the
Application Server based on the Routing (Link) Key, it selects an ASP that is
active for the AS according to a Traffic Mode Type that is associated with the
AS.  The Traffic Mode Type describes three general distribution algorithms:
Override, Loadshare and Broadcast.
.lp
The detailed actions taken for these distribution algorithms are described in
Section 4 of the Signalling User Adaptation Layer specifications;
.[
RFC 3057
.]
.[
dua-00
.]
.[
v5ua-01
.]
.[
m2ua-11
.]
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
however, they can be summarized as follows:
.lp
.b "Traffic Mode Type Override:\-\ "
.ix +\n(iiu
When distributing messages to an Override Application Server, the SGP selects
the ASP which is active for the Application Server.  In an Override
Application Server, at most one ASP can be active for the AS at any given point
in time.  The active ASP for the AS is selected.
.lp
.b "Traffic Mode Type Loadshare:\-\ "
.ix +\n(iiu
When distributing messages to a Loadshare Application Server, the SGP selects
one of the ASPs that are active for the Application Server using an
implementation dependent loadsharing algorithm based on some unspecified
aspect of the traffic or static configuration data.
.lp
.b "Traffic Mode Type Broadcast:\-\ "
.ix +\n(iiu
When distributing messages to a Broadcast Application Server, the SGP sends a
copy of the message to each of the ASPs that are active for the Application
Server.  (The ASPs themselves decide which, if any, of the ASPs will process
the message.)
.lp
In general, for the Signalling User Adapatation Layers, the Traffic Mode Type
is a characteristic of the Application Server, and an Application Server can
only have associated with it only one Traffic Mode Type, and thus, only one
traffic distribution algorithm can be used across the ASPs that are serving a
given Application Server.
.lp
This extension document enhances the traffic distribution algorithms of the
existing Signalling User Adaptation Layers by introducing an additional level
of distribution.
.sh 3 "Extended Traffic Distribution"
.(z
.(c
.nf
.sz -2
\fC\
                             ____    ____
           Traffic    Load  /....\\  /....\\
           Mode Type  Group|...___||__....|
 _______                   |..|       |...|
|       |---+---------------->|  ASP  |...|
|  SGP  |    \\             |..|_______|...|
|_______|-\\   \\            |...___||__....|
           \\   \\           |..|       |...|
            \\   \\------------>|  ASP  |...|
 _______    |              |..|_______|...|
|       |   |              |......||......| Application
|  SGP  |   |               \\____/ |......| Server
|_______|   |                ____  |......|
            |         Load  /....\\ |......|
            |         Group|...___||__....|
            |              |..|       |...|
            +---------------->|  ASP  |...|
             \\             |..|_______|...|
              \\            |...___||__....|
               \\           |..|       |...|
                \\------------>|  ASP  |...|
                           |..|_______|...|
                           |......||......|
                            \\____/  \\____/
.sz +2
.)c
.#f "Load Group Traffic Distribution"
.)z
.lp
\fI\*(&f\n(&p\fR illustrates the extended traffic distribution algorithms that
are used across the Signalling User Adaptation Layers as a result of the
messages and procedures in this extension.
.lp
This extension introduces the concept of a \fI\)Load Group\fR.  A \fI\)Load
Group\fR is a logical grouping of Application Server Processes (ASPs) into
traffic groups serving an Application Server.
Signalling Gateway Processes (SGPs) distribute traffic first over \fI\)Load
Groups\fR and then distribute traffic within the \fI\)Load Group\fR.  Each
\fI\)Load Group\fR describes and is identified by a \fI\)Load Selection\fR
.[
loadsel
.]
within the Application Server.  The \fI\)Load Selection\fR identifies the
traffic flows that will be distributed to an associated \fI\)Load Group\fR
within an Application Server.
.lp
When an SGP distributes a Signalling User Adaptation Layer message towards an
Application Server based on the Routing (Link) Key, it first selects an
\fI\)Load Group\fR that is active for the Application Server according a
traffic distribtuion algorithm determined by the \fI\)Load Distribution\fR
that is associated with the Application Server and the \fI\)Load Selection\fR
position of the \fI\)Load Group\fR within the AS.
.lp
The Traffic Mode Type continues to describe three general distribution
algorithms: Override, Loadshare and Broadcast.  The change in the behavior of
the SGP when selecting an ASP for traffic distribution introduced by this
extension is that the SGP also takes into account the concept of a \fI\)Load
Group\fR as identified within an AS by its \fI\)Load Selection\fR.
.lp
The extended procedures can be summarized as follows:
.lp
.b "Traffic Mode Type Override:\-\ "
.ix +\n(iiu
When distributing messages to an Override Application Server, the SGP first
selects the \fI\)Load Group\fR that is active for the Application Server.  In
an Override Application Server, at most one \fI\)Load Group\fR can be active
for the AS at any given point in time.  The active \fI\)Load Group\fR for the
AS is selected.
.lp
.b "Traffic Mode Type Loadshare:\-\ "
.ix +\n(iiu
When distributing messages to a Loadshare Application Server, the SGP selects
one of the \fI\)Load Groups\fR that are active for the Application Server
using an implementation dependent loadsharing algorithm based on the \fI\)Load
Selection\fR
.[
loadsel
.]
associated with the \fI\)Load Group\fR.
.lp
.b "Traffic Mode Type Broadcast:\-\ "
.ix +\n(iiu
When distrbuting messages to a Broadcast Application Server, the SGP sends a
copy of the message to each of the \fI\)Load Groups\fR that are active for the
Application Server.  (The \fI\)Load Groups\fR themselves decide which, if any,
of the \fI\)Load Groups\fR will process the message.)
.lp
After selecting an \fI\)Load Group\fR according to the \fI\)Traffic Mode
Type\fR for the Application Server, the SGP then selects an ASP within the
\fI\)Load Group\fR based on the \fI\)Load Distribution\fR that is associated
with the \fI\)Load Group\fR.  The \fI\)Load Distribution\fR describes the same
three general distribution algorithms that are provided in the \fI\)Traffic Mode
Type:\fR Override, Loadshare and Broadcast.  When selecting an active ASP
within a \fI\)Load Group\fR, the procedures that the SGP will follow can be
summarized as follows:
.lp
.b "Load Distribution Override:\-\ "
.ix +\n(iiu
When distributing messages within an Override Load Group, the SGP selects the
ASP which is active for the Load Group.  In an Override Load Group, at most
one ASP can be active for the \fI\)Load Group\fR at any given point in time.
The active ASP for the \fI\)Load Group\fR is selected.
.lp
.b "Load Distribution Loadshare:\-\ "
.ix +\n(iiu
When distributing messages within a Loadshare Load Group, the SGP selects one
of the ASPs that are active for the Load Group using an implementation
dependent loadsharing algorithm based on some unspecified aspect of the
traffic or static configuration data.
.lp
.b "Load Distribution Broadcast:\-\ "
.ix +\n(iiu
When distributing messages within a Broadcast Load Group, the SGP sends a copy
of the message to each of the ASPs that are active for the Load Group.  (The
ASPs themselves decide which, if any, of the APSs will process the message.)
.lp
The result of this extension is that two levels of traffic distribution are
provided for, permitting more flexible membership of ASPs serving Application
Servers, and provides the Application Server Process with more control over
the traffic patterns for which it is active.
.sh 2 "Sample Configurations"
.lp
Although this extension does not restrict either Traffic Mode Type or Load
Distribution to a static assignment, there are, for example, six (6)
combinations of static Traffic Mode Type and Load Distribution assignment
under this scheme.  Not all of these combinations provide for interesting or
useful configurations as follows:
.(b L
.#t "Sample Configurations"
.TS
box center tab(:);
cb1|cb1|cb1|lb
cb|cb|cb|lb
cb|cb|cb|lb
n|l|l|lw(3.8i).
:Traffic:Load:
Mode:Mode:Distri-:Description
:Type:bution:
=
1:Override:Loadshare:T{
.#v
This mode permits a loadshare group of ASPs to override another loadshare
group of ASPs.
T}
_::_:_
2::Broadcast:T{
.#v
This mode allows "mirrored" ASPs to override each other.
T}
_
3:Loadshare:Override:T{
.#v
This mode allows ASPs to override each other within a traffic slot of a
loadshare group.
T}
_::_:_
4::Broadcast:T{
.#v
This mode permits "striping" and "mirroring" with loadsharing under ASP
control.
T}
_
5:Broadcast:Override:T{
.#v
This mode permits a joining ASP to knock another ASP out of a Broadcast slot
for an Application Server.
T}
_::_:_
6::Loadshare:T{
.#v
This mode permits "mirroring" and "striping" including automatic loadsharing
within a mirror image.
T}
.TE
.)b
.sh 1 "Conventions"
.lp
The keywords \fB\)MUST\fR, \fB\)MUST NOT\fR, \fB\)REQUIRED\fR, \fB\)SHALL\fR,
\fB\)SHALL NOT, \fB\)SHOULD\fR, \fB\)SHOULD NOT\fR, \fB\)RECOMMENDED\fR,
\fB\)NOT RECOMMENDED\fR, \fB\)MAY\fR, and \fB\)OPTIONAL\fR, when they appear
in this document, are to be interpreted as described in.
.[
key words
.]
.sh 1 "Protocol Elements"
.lp
The following subsections describe the parameters which are added by this
extension, their format and the message in which they are used.
.sh 2 "Parameters"
.lp
This extension adds one new parameter: the \fI\)Load Distribution\fR
parameter.
.sh 3 "Load Distribution"
.lp
The \fI\)Load Distribution\fR parameter is used in the \fI\)REQ REQ\fR, \fI\)REQ
RSP\fR, \fI\)ASPAC\fR and \fI\)ASPAC ACK\fR messages.  It is used in
conjunction with the \fI\)Traffic Mode Type\fR parameter
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
and \fI\)Load Selection\fR parameter
.[
loadsel
.]
to further refine the traffic distribution algorithm for an ASP in a \fI\)Load
Group\fR serving an Application Server.  The \fI\)Load Selection\fR parameter
identifies the \fI\)Load Group\fR for which the ASP is registering, activating
or deactivating and the \fI\)Load Distribution\fR parameter identifies the
traffic distribution that is to be used within the \fI\)Load Group\fR.
.lp
The \fI\)Load Distribution\fR parameter is formatted as follows:
.(b
.(c
.nf
.sz -2
\fC\
 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0xXXXX          |          Length = 8         |
+---------------------------------+-----------------------------+
|                        Load Distribution                      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
.sz +2
.)c
.)b
.(q
.#v
\fB\)EDITOR'S NOTE:\-\fR\  The parameter tag values shown as \f(CB\)0xXXXX\fR
above will be assigned by IANA within the common parameter range of the
SIGTRAN UAs and may change its value in further versions of this document.
.)q
.lp
The \fI\)Load Distribution\fR parameter contains the following fields:
.ip "Load Distribution field: n x 32-bits (unsigned integer)" 2

THe \fI\)Load Distribution\fR has the same purpose for the \fI\)Load Group\fR
that the \fI\)Traffic Mode Type\fR has for the Application Server: it
identifies the traffic distribution algorithm to be used within the \fI\)Load
Group\fR.  Valid values for \fI\)Load Distribution\fR are as follows:
.ix +4
.TS
tab(:);
nl.
1:Override
2:Loadshare
3:Broadcast
.TE
.sh 2 "Messages"
.ds #u \*#
.lp
This extension adds the \fI\)Load Distribtution\fR parameter as an
\fB\)OPTIONAL\fR parameter to be used in conjunction with the common
\fI\)Traffic Mode Type\fR in the following messages: \*#
.(d
.ip \*#
For a detailed description of these messages, see Section 3 of
M3UA, SUA and TUA.
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
.)d
.ix +4
.TS
tab(:);
lil.
REG REQ:Registration Request message
ASPAC:ASP Active message
ASPAC Ack:ASP Active Ack message
.TE
.sh 3 "Registration Request (REG REQ)"
.lp
This extension supplements the \fI\)Registration Request (REG REQ)\fR message
by permitting the following optional parameters to be included in the
\fI\)Routing Key\fR
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
parameter or \fI\)Link Key\fR
.[
rfc 3057
.]
.[
dua-00
.]
.[
v5ua-01
.]
.[
m2ua-11
.]
parameter within the message:
.ix +4
.TS
tab(:);
lbss
lw(2.5i)lc.
Extension Subparameters
_
Load Distribution:Optional:
.TE
.ix -4
.lp
The \fI\)Load Distribution\fR parameter is used in the Routing (Link) Key to
further refine the traffic distribution to be received by the registering ASP.
.lp
The format of the resulting \fI\)Routing Key\fR or \fI\)Link Key\fR parameter
is as follows:
.(b
.(c
.nf
.sz -2
\fC\
 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Local-RK(LK)-Identifier                   |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                  Traffic Mode Type (optional)                 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                    Load Selection (optional)                  |
\f(CB\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                  Load Distribution (optional)                 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
\f(CR\
\\                                                               \\
/                          Routing Context                      /
\\                                or                             \\
/                       Interface Identifier(s)                 /
\\                                                               \\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
.sz +2
.)c
.)b
.lp
No other changes to the \fI\)REG REQ\fR message, \fI\)Routing Key\fR or
\fI\)Link Key\fR parameters format are provided by this extension\*(#u.
.lp
When an ASP wishes to register within a \fI\)Load Group\fR associated with an
Application Server, it includes the \fI\)Load Selection\fR parameter
and \fI\)Load Distribution\fR in the \fI\)Routing (Link) Key\fR for that
Application Server in the \fI\)REG REQ\fR message.
.lp
The \fI\)Load Distribtuion\fR parameter indicates the traffic distribution
method to be used within the \fI\)Load Group\fR as identified by the Load
Selection.
.sh 3 "Registration Response (REG RSP)"
.lp
This extension adds the following \fI\)Registration Status\fR values to the
\fI)Registration Status\fR field in the \fB\)REG RSP\fR message:
.ix +4
.TS
tab(:);
nl.
0xZZ:Error - Unsupported/Invalid Load Distribution
.TE
.ix -4
.(q
.#v
\fB\)EDITOR'S NOTE:- \fR The \fI\)Registration Status\fR value shown as
\f(CR\)0xZZ\fR) above will be assigned by IANA as a value of the UA-specific
\fI\)Registration Status\fR parameter for each SIGTRAN UA and may change its
value in further versions of this document.
.)q
.sh 3 "ASP Active (ASPAC)"
.lp
This extension supplements the \fB\)ASPAC\fR message by permitting the
following optional parameters to be included in the message:
.ix +4
.TS
tab(:);
lbss
lw(2.5i)lc.
Extension Parameters
_
Load Distribution:Optional:
.TE
.ix -4
.lp
The format of the resulting \fI\)ASPAC\fR message is as follows:
.(b
.(c
.nf
.sz -2
\fC\
 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0x000b          |          Length = 8         |
+---------------------------------+-----------------------------+
|                         Traffic Mode Type                     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0x001d          |          Length = 8         |
+---------------------------------+-----------------------------+
\\                                                               \\
/                         Load Selection(s)                     /
\\                                                               \\
\f(CB\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0xXXXX          |          Length = 8         |
+---------------------------------+-----------------------------+
|                         Load Distribution                     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
\f(CR\
\\                                                               \\
/                          Routing Context                      /
\\                                or                             \\
/                       Interface Identifier(s)                 /
\\                                                               \\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0x0004          |          Length             |
+---------------------------------+-----------------------------+
\\                                                               \\
/                            Info String                        /
\\                                                               \\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
.sz +2
.)c
.)b
.(q
.#v
\fB\)EDITOR'S NOTE:\-\fR\  The parameter tag values shown as \f(CB\)0xXXXX\fR
above will be assigned by IANA within the common parameter range of the
SIGTRAN UAs and may change its value in further versions of this document.
.)q
.lp
No other changes to the \fB\)ASPAC\fR message format are provided by this
extension\*(#u.
.lp
When an ASP wishes to activate only within a \fI\)Load Group\fR associated
with an Application Server, it includes the \fI\)Load Selection\fR
and \fI\)Load Distribtuion\fR parameters in the \fB\)ASPAC\fR message.
.lp
The \fI\)Load Distribtuion\fR parameter indicates the traffic distribution
method to be used within the \fI\)Load Group\fR as identified by the Load
Selection.
.sh 3 "ASP Active Ack (ASPAC ACK)"
.lp
This extension supplements the ASPAC ACK message by permitting the following
optional parameters to be included in the message:
.ix +4
.TS
tab(:);
lbss
lw(2.5i)lc.
Extension Parameters
_
Load Distribution:Optional:
.TE
.ix -4
.lp
The format of the resulting \fI\)ASPAC ACK\fR message is as follows:
.(b
.(c
.nf
.sz -2
\fC\
 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0x000b          |          Length = 8         |
+---------------------------------+-----------------------------+
|                         Traffic Mode Type                     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0x001d          |          Length = 8         |
+---------------------------------+-----------------------------+
\\                                                               \\
/                         Load Selection(s)                     /
\\                                                               \\
\f(CB\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0xXXXX          |          Length = 8         |
+---------------------------------+-----------------------------+
|                         Load Distribtuion                     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
\f(CR\
\\                                                               \\
/                          Routing Context                      /
\\                                or                             \\
/                       Interface Identifier(s)                 /
\\                                                               \\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Tag = 0x0004          |          Length             |
+---------------------------------+-----------------------------+
\\                                                               \\
/                            Info String                        /
\\                                                               \\
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
.sz +2
.)c
.)b
.(q
.#v
\fB\)EDITOR'S NOTE:\-\fR\  The parameter tag values shown as \f(CB\)0xXXXX\fR
above will be assigned by IANA within the common parameter range of the
SIGTRAN UAs and may change its value in further versions of this document.
.)q
.lp
No other changes to the \fB\)ASPAC ACK\fR message format are provided by this
extension\*(#u.
.lp
When an ASP has requested activation within a \fI\)Load Group\fR or the SG
otherwise activates the ASP within a \fI\)Load Group\fR the SG responds with
an \fB\)ASPAC ACK\fR message including the \fI\)Load Selection\fR that
identifies the \fI\)Load Group\fR and optionally includes the \fI\)Load
Distribution\fR for the \fI\)Load Group\fR in which the ASP has been
activated.  If the ASP included the \fI\)Load Distribution\fR parameter in the
\fB\)ASPAC\fR message, the SG \fB\)MUST\fR include the \fI\)Load
Distribution\fR parameter in the response \fB\)ASPAC ACK\fR message.
.lp
The \fI\)Load Distribtuion\fR parameter indicates the traffic distribution
method to be used within the \fI\)Load Group\fR as identified by the Load
Selection.
.lp
.sh 3 "Error (ERR)"
.lp
This extension supplements the \fB\)Error (ERR)\fR message by adding the
following values to the common mandatory \fI\)Error Code\fR parameter in the
\fB\)ERR\fR message:
.ix +4
.TS
tab(:);
nl.
0xYY:Invalid/Unsupported Load Distribution
.TE
.ix -4
.(q
.#v
\fB\)EDITOR'S NOTE:- \fR The \fI\)Error Code\fR value shown throughout this
document as \f(CR\)0xYY\fR) will be assigned by IANA as a value of the common
\fI\)Error Code\fR parameter for SIGTRAN UAs and may change its value in
further versions of this document.
.)q
.lp
This new error code is interpreted as follows:
.lp
The \fI\)"Invalid/Unsupported Load Distribution"\fR error
.ix +4
would be sent by an SGP if an ASP sends an ASP Active with an invalid or
unsupported Load Distribution.  An example would be a case in which
the SGP did not support override within a \fI\)Load Group\fR.
.lp
No other changes to the \fB\)ERR\fR message or \fI\)Error Code\fR parameter
values are provided by this extension.  See Section 4 for extension
procedures associated with the \fB\)ERR\fR message.
.sh 1 "Procedures"
.lp
This \fI\)Load Grouping\fR extension provides for an additional level of
control over the traffic distribution patterns within an Application Server.
This extension provides the \fI\)Load Distribution\fR parameter which may be
optionally included in the \fB\)REG REQ\fR, \fB\)ASPAC\fR and \fB\)ASPAC
ACK\fR messages.  In addition, it supplements the ASP State Maintenance and
ASP Traffic Maintenance procedures.
.sh 2 "ASP State Maintenance"
.lp
In addition to the SGP mainting the state of each remote ASP in each
Application Server that the ASP is configured to receive traffic, under this
extension, the SGP \fB\)MAY\fR also maintain the state of each remote ASP in
each \fI\)Load Group\fR within an Application server that the ASP is
configured to receive traffic.  The \fI\)Load Group\fR state is maintained
separate from the ASP and AS states.
.sh 3 "Load Group State"
.lp
The state of the \fI\)Load Group\fR is maintained in the Signalling User
Adaptation Layer on the SGPs.  The state of the \fI\)Load Group\fR changes due
ASP state transitions.  The possible states of a \fI\)Load Group\fR are:
.ip "\fB\)LG-DOWN\fR:" 16
The \fI\)Load Group\fR is unavaialble.  This state implies that all related
ASPs are in the \fB\)ASP-DOWN\fR state for this \fI\)Load Group\fR.
Initially, the \fI\)Load Group\fR will be in this state.
.ip "\fB\)LG-INACTIVE\fR:" 16
The \fI\)Load Group\fR is available but no application traffic is active (i.e,
one or more related ASPs are in the \fB\)ASP-INACTIVE\fR state, but none are
in the \fB\)ASP-ACTIVE\fR state within the \fI\)Load Group\fR).
.ip "\fB\)LG-ACTIVE\fR:" 16
The \fI\)Load Group\fR is available and application traffic is active.  This
state implies that at least one ASP is in the \fB\)ASP-ACTIVE\fR state within
the \fI\)Load Group\fR.
.sh 3 "Application Server State"
.lp
Where ASPs are configured to operation within \fI\)Load Groups\fR under this
extension, the Application Server state is interpreted as provided in the
Signalling User Adaptation Layer specifications.
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
.sh 2 "ASP Traffic Maintenance"
.sh 3 "ASP Active Procedures"
.lp
This \fI\)Load Grouping\fR extension supplements the ASP Active Procedures as
follows:
.lp
When an ASP sends an \fB\)ASPAC\fR message to activate the ASP within an
Application Server, the ASP \fB\)MAY\fR choose to activate within a \fI\)Load
Group\fR for the specified AS by including the \fI\)Load Selection\fR
parameter in the \fB)ASPAC\fR message.
.lp
When an SGP receives an \fB\)ASPAC\fR message with a \fI\)Load Selection\fR
parameter in the message, or where the SGP is otherwise configured to activate
the ASP in a configured \fI\)Load Group\fR, when the SGP moves the ASP to the
ASP-ACTIVE state for the AS, it also moves the ASP to the ASP-ACTIVE state for
the \fI\)Load Group\fR identified by the \fI\)Load Selector\fR field in the
\fI\)Load Selection\fR parameter.  In either case, if the activation is
successful, the SGP includes the \fI\)Load Selection\fR parameter in the
\fB\)ASPAC ACK\fR message.
.lp
If the \fI\)Load Selector\fR in the \fB\)ASPAC\fR message is invalid, the SGP
responds with ERR("Error - Invalid Load Selector").  If the \fI\)Load
Selection\fR parameter is not present in the \fB\)ASPAC\fR message and the SGP
is configured to require one, or the \fI\)Load Selector\fR field is not valid
or unconfigured for the Application Server, the SGP responsds with ERR("Error
- Unsupported/Unconfigured/Missing Load Selector").  If the \fI\)Load
Selection\fR parameter contains an invalid or unsupported \fI\)Load
Distribution\fR value, or the \fI\)Load Selection\fR parameter is missing but
the SGP cannot determine the distribution applicable to the \fI\)Load Group\fR
without one, the SGP response with ERR("Error - Invalid/Unsupported/Missing
Load Distribution").
.lp
There are three modes of Application Server traffic handling in the SGP at the
Application Server level and three modes of AS traffic handling at the Load
Group level: Override, Loadshare and Broadcast.  When included, the
\fI\)Traffic Mode Type\fR parameter in the \fB\)ASPAC\fR message indicates the
traffic handling mode to be used in a particular Application Server between
Load Groups.  When included, the \fI\)Load Distribution\fR field in the
\fI\)Load Selection\fR parameter indicates the traffic handling mode to be
used between ASPs within a Load Group.
.lp
In the case of an Override mode AS, reception of an ASP Active message at an
SGP may move a \fI\)Load Group\fR to the LG-ACTIVE state.  When an LG moves
to the LG-ACTIVE state in an Override mode AS, this causes the (re)direction
of all traffic for the AS to the active Load Group.
Distribution of traffic within the Load Group is determine on the basis of the
Load Distribution mode of the Load Group.
Any previously active Load Group is now considered to be in state LG-INACTIVE
and \fB\)SHOULD\fR no longer receive traffic from the SGP within the AS.
The SGP then \fB\)MUST\fR send a Notify message ("Alternate ASP Active") and
include the \fI\)Load Selection\fR parameter in the Notify message indicating
the \fI\)Load Group\fR that has become active.
.lp
In the case of a Loadshare mode AS, the reception of an ASP Active message at
an SGP that moves a \fI\)Load Group\fR to the LG-ACTIVE state causes the
direction of specific traffic flows associated with the \fI\)Load Selector\fR
to the \fI\)Load Group\fR.  The assignment of traffic flows to \fB\)Load
Selector\fR values is implementation depenedent, but could be based on
specific information in the protocol data message.
.lp
In the case of a Broadcast mode AS, reception of an ASP Active message at an
SGP that results in moving a \fI\)Load Group\fR to the LG-ACTIVE state within
the AS causes the direction of traffic to the newly active \fI\)Load Group\fR
in addition to all the other LGs that are currently active for the AS.  The
algorithm at the SGP for broadcasting traffic within an AS to all the active
ASPs is a simple broadcast algorithm, where every message is sent to each of
the active Load Groups.
.sh 3 "ASP Inactive Procedures"
.lp
This \fI\)Load Grouping\fR extension supplements the ASP Active procedures of
the UAs as follows:
.lp
When an ASP wishes to withdraw from a specific \fI\)Load Group\fR within an
Application Server, the ASP sends an ASP Inactive message to the SGP with a
\fI\)Load Selection\fR parameter included in the message.  In the case where
the ASP does not include the \fI\)Load Selection\fR parameter in the ASP
Inactive message, the SGP must know via configuration data which Load Groups
the ASP is a member.  Upon receiving an ASP Inactive message with included
or implied \fI\)Load Selection(s)\fR, the SGP moves the ASP to the
ASP-INACTIVE state in each of the Load Groups indicated.
.lp
.lp
.lp




.sh 2 "Registration"
.lp
UAs permit Application Server Processes to register for the Routing Context
(Interface Identifier) associated with a Routing Key (Link Key).  This draft
extends the registration procedure to also permit the Application Server
Process to register for a \fI\)Load Group\fR identifier in addition to the
Routing Contex/Interface Id.  This is performed using a \fI\)Load Group\fR which
has the same form as the Routing Key, but has some additional fields which are
only applicable to Loadsharing.
.lp
In addition to the normal registration procedures of the UAs, the following
additional error conditions can occur:
.ip "\fI""Error - Invalid Load Group""\fR"
This error \fB\)MUST\fR be sent in an \fI\)Error (ERR)\fR message if the SG
determines that the Load Group is invalid.
.ip "\fI""Error - Unsupported/Unconfigured Load Group""\fR"
This error \fB\)MUST\fR be sent in an \fI\)Error (ERR)\fR message whenever the
SG determines that the Load Group provided in a \fI\)REG REQ\fR message has
not be configured and the SG does not support dynamic allocation of Load
Selectors for the specified Key, and \fB\)MUST\fR be sent in an \fI\)Error
(ERR)\fR message whenever the SG determines that the Load Group provided in
a \fI\)REG REQ\fR message is not supported by the SG.
.ip "\fI""Error - Invalid/Unsupported/Missing Load Distribution""\fR"
This error \fB\)MUST\fR be sent in an \fI\)Error (ERR)\fR message whenever the
SG determines that the Load Distribution associated wtih a Load Group is
invalid, is not supported by the SG, or is required to determine the Load
Distribution algorithm of the \fI\)Load Group\fR but is missing from
the Load Group in the \fI\)REG REQ\fR message.
.sh 2 "ASP Activation"
.lp
When activating, this draft extends the UA activation procedures by permitting
an optional \fI\)Load Selection\fR parameter to be included in the ASP Active
(ASPAC) and ASP Active Ack (ASPAC Ack) messages.  The \fI\)Load Selection\fR
parameter is used to indicate for which \fI\)Load Group\fR the
concerned Application Server is becoming active.
.lp
Whenever the SG is unable to activate the ASP within the selected Application
Server \fI\)Load Group\fR, the SG \fB\)MUST\fR reply with an
\fI\)Error (ERR)\fR message containing one of the errors defined in the UA
documents\*(#u, or one of the following additional errors:
.ip "\fI""Error - Invalid Load Group Identifier""\fR"
.sh 2 "ASP Deactivation"
.lp
When deactivating, this draft extends the UA activation procedures by
permitting an optional \fI\)Load Selection\fR parameter to be included in the
ASP Inactive (ASPIA) and ASP Inactive Ack (ASPIA Ack) message.  The \fI\)Load
Selection\fR parameter is used to indicate for which traffic in the \fI\)Load
Group\fR the concerned Application Server is becoming inactive.
.sh 2 "ASP Failure"
.lp
When an ASP fails that was supporting load-sharing application servers, the
NTFY("ASP Failure")
.sh 2 "ASP Override"
.sh 2 "Notification"
.lp
When the SGP or IPSP notifies its UA peer with a NTFY messages which concerns
an ASP, it \fB\)MUST\fR include the \fI\)Load Group\fR (if available)
along with the ASP Identifier in the message.  The NTFY messages to which this
applies are:
.ip "\fI\)NTFY(""ASP Failure"") \-\fR"
When the SGP or IPSP notifies the active and inactive ASPs in an AS that it
has detected the failure of an ASP or the failure of an association to an ASP
(i.e. SCTP Communication Lost Indication), it \fB\)MUST\fR include the
\fI\)Load Group\fR (if available) with the ASP Identifier in the message.
When the Routing Context(s)/Interface Identifier(s) associated with the
Application Servers cannot be implied at the ASP from static configuration
data, the Routing Context/Interface Identifier(s) \fB\)MUST\fR also be placed
in the NTFY("ASP Failure") message.  The notifying SGP or IPSP \fB\)MAY\fR
also place the \fI\)Load Selection\fR parameter into the NTFY("ASP Failure")
message to indicate the traffic which was applicable to the load selection at
the time of the failure.

The purpose of this procedure is to inform the active and inactive ASPs, not
only of the ASP failure, but of the identity of the ASP and the load selection
for which the failed ASP was responsible.
.ip "\fI\)NTFY(""Alternate ASP Active in AS"") \-\fR"
When the SGP or IPSP notifies the previously active ASP in a override AS that
an alternate ASP has become active using the NTFY("Alternate ASP Active in
AS") message, it \fB\)MUST\fR include the \fI\)Load Group\fR (if
available) with the ASP Identifier in the message.
.lp
The purpose of this procedure is to inform the previously active ASP, not only
of the that another ASP has taken over the traffic for which the notified ASP
was previously responsible, but to also indicate the identify of the
overriding ASP and the load selection that was overridden.
.sh 1 "Security"
.sh 1 "IANA Considerations"
.lp
This extension adds the following parameter tag value (described in Section 3)
to the Common Parameter numbering space for the UAs.
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
.ix +4
.TS
tab(:);
nl.
0xXXXX:Load Distribution
.TE
.ix -4
.(q
.#v
\fB\)EDITOR'S NOTE:\-\fR\  The \fI\)Load Distribution\fR parameter tag value
shown throughout this document as \f(CB\)0xXXXX\fR will be assigned by IANA
within the common parameter range of the SIGTRAN UAs and may change its value
in further versions of this document.
.)q
.lp
This extension adds the following value to the \fI\)Error Code\fR parameter of
the UAs.
.ix +4
.TS
tab(:);
nl.
0xYY:Invalid/Unsupported Load Distribution
.TE
.ix -4
.(q
.#v
\fB\)EDITOR'S NOTE:- \fR The \fI\)Error Code\fR value shown as \f(CR\)0xYY\fR)
above will be assigned by IANA as a value of the common \fI\)Error Code\fR
parameter for SIGTRAN UAs and may change its value in further versions of this
document.
.)q
.lp
This extension adds the following value to the \fI\)Registration Status\fR
field of the \fI\)Registration Result\fR parameter for the UAs.
.[
m3ua-10
.]
.[
sua-09
.]
.[
tua-01
.]
.ix +4
.TS
tab(:);
nl.
0xZZ:Error - Invalid/Unsupported Load Distribution
.TE
.ix -4
.(q
.#v
\fB\)EDITOR'S NOTE:- \fR The \fI\)Registration Status\fR value shown as
\f(CR\)0xZZ\fR) above will be assigned by IANA as a value of each UA-specific
\fI\)Registration Status\fR parameter for each SIGTRAN UA and may change its
value in further versions of this document.
.)q
.sh 1 "Acknowledgements"
.lp
The authors would like to thank
Ken Morneault,
Barry Nagelberg,
Benjamin J. Wilson,
Jacques Rajchgod,
Greg Sidebottom
and
Gery Verwimp
for their valuable comments and suggestions.
.sh 1 "Author's Addresses"
.lp
.TS
expand tab(;);
lr.
Brian Bidulock;Phone: +1-972-839-4489
OpenSS7 Corporation;Email: bidulock@openss7.org
4701 Preston Park Boulevard;
Suite 424;
Plano, TX  75093;
USA;
.TE
.bl 3
.lp
This draft expires July, 2002.
.bp
.nr ii 0.5i
.uh "Endnotes"
.pd
.de ]<
.uh "References"
.rm (f )f
..
.[
$LIST$
.]
.bp
.ce 1
.uh "List of Tables"
.(l I
.xp 3
.)l
.ce 1
.uh "List of Illustrations"
.(l I
.xp 2
.)l
.ce 1
.uh "Table of Contents"
.(l I
.xp 0
.)l
.bp
.uh "Copyright Statement"
.lp
\fBCopyright \(co The Internet Society (2002).  All Rights Reserved.\fR
.lp
This document and translations of it may be copied and furnished to others,
and derivative works that comment on or otherwise explain it or assist in its
implementation may be prepared, copied, published and distributed, in whole or
in part, without restriction of any kind, provided that the above copyright
notice and this paragraph are included on all such copies and derivative
works.  However, this document itself may not be modified in any way, such as
by removing the copyright notice or references to the Internet Society or
other Internet organizations, except as needed for the purpose of developing
Internet standards in which case the procedure for copyrights defined in the
Internet Standards process must be followed, or as required to translate into
languages other than English.
.lp
The limited permission granted above are perpetual and will not be revoked by
the Internet Society or its successors or assigns.
.lp
This document and the information contained herein is provided on an "AS IS"
basis and \fB\)THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE
DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY
WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS
OR ANY IMPLIED WARRANTIES OF MECHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE.
