product hiq 6200 v2.1_hie

[@Project][@customer]

Information and Communication Networks

[@File-Name] P R O D U C T D E S C R I P T I O N of 22

[@Cust-Ref-No.] [@Proposal-No.] 10.10.2003

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Product DescriptionSURPASS hiQ 6200

SIP Registrar Proxy and RedirectServer V2/V2.1



Table of Contents Page

1 Introduction......................................................................................................................4

2 Functional Description..................................................................................................6

2.1 Version 2.0 enhancements...........................................................................................6

2.2 Version 2.1 enhancements...........................................................................................6

2.3 Registrar.......................................................................................................................7

2.4 Proxy............................................................................................................................8

2.5 Redirect........................................................................................................................8

2.6 Routing Capabilities......................................................................................................9

2.7 Interface to the PSTN/ISDN Gateway..........................................................................9

2.8 Support SIP-T/SIP-I....................................................................................................10

2.9 Switching off authentication from trusted gateways and proxies................................10

2.10 Interface to the PRI Gateway..................................................................................10

2.11 Interface to presence server...................................................................................11

2.12 Interface to IP-IP Gateway......................................................................................11

2.13 Interworking with voice and video conferencing server...........................................11

2.14 Overload Protection................................................................................................11

2.15 Service based Charging..........................................................................................12

2.16 Call Diversion..........................................................................................................12

3 Software Architecture..................................................................................................14

4 Hardware Architecture.................................................................................................16

5 Management.................................................................................................................17



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5.1 Overview.....................................................................................................................17

5.2 Security.......................................................................................................................18

5.3 Alarming and Statistics...............................................................................................18

6 Security.........................................................................................................................19

7 Technical Data..............................................................................................................20

7.1 General.......................................................................................................................20

7.2 Performance...............................................................................................................20

7.3 Reliability....................................................................................................................20

7.4 Compliance to Standards...........................................................................................21

8 Abbreviations.................................................................................................................22

List of Figures:

Figure 1-1: SIP in Release SIP 2.0.......................................................................................4

Figure 1-2 SIP in Release SIP 2.1.........................................................................................5

Figure 3-1 hiQ 6200 software architecture........................................................................14

Figure 4-1 Sun Netra 120....................................................................................................16



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1 Introduction

The hiQ 6200 SIP Registrar, Proxy and Redirect Server is the gatekeeper for SIP based

subscribers in a SURPASS network. It provides services for subscriber registration and

routing of session requests for SIP User Agents (UA). Together with other elements of the

SURPASS solution like the hiQ 30 LDAP server and the SIGMA voice and video PC client,

the hiQ 6200 can provide voice and video communications over Internet Protocol for data

subscribers. As part of the overall SURPASS SIP solution, the hiQ 6200 communicates with

subscriber UA’s, with other hiQ 6200 or third vendor SIP servers (Voice- and Video

Conferencing, Presence Server). The subscriber UA’s can be SIP phones or SIP software

clients on any kind of Internet terminal.

It communicates with a UA entity in the SURPASS hiQ 9200 Soft Switch via SIP Network to

Network Interface (SIP NNI) in order to provide an access to IP subscribers to the PSTN

and Intelligent Networks. In the next version it communicates with the PRI Gateway INALP

IPNode 2300 to provide a cost optimized access to IP subscribers to the PSTN Networks.

A typical configuration in a SIP-only domain solution is shown in figure 1.



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Figure 1-1: Solution SIP_2.0

With the inclusion of the PRI Gateway and Application Servers in with SIP solution V2.1, the

configuration looks as follows:

Figure 1-2 SIP solution SIP_2.1



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2 Functional Description

The SURPASS hiQ 6200 encompasses the main functions of UA Registration, Proxy SIP

method handling and Redirect SIP method handling. It works as Proxy and Registrar or

Redirect and Registrar Server. It interfaces with the hiQ 9200 Soft Switch (SIP_2), PRI

Gateway INALP IPNode 2300 (SIP_2.1), IP-IP Gateway and application servers for

Presence, Voice and Video conferencing (SIP_2.1). With solution SIP_2.2 we offer the

interface to hiE 9200 mediation switch. These functions are described in detail in the next

sections IP-IP Gateway, and application servers for Presence, Voice and Video

conferencing (SIP_2.1).

2.1 Version 2.0 enhancements

In version 2.0 of the hiQ 6200 Proxy/Redirect and Registrar server, the following

enhancements are introduced:

HW SUN Netra 120

Overload Protection with alarming

SIP stack conformance to RFC3261

Time-of-day dependent routing

Weighted routing to different servers

Routing to PSTN/ISDN Gateway

Support SIP-T, SIP-I

Switching off authentication for trusted gateways and proxies

2.2 Version 2.1 enhancements

In version 2.1 of the hiQ 6200 Proxy/Redirect and Registrar server, the following

enhancements are introduced:



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Interface to Presence Server

Interface to PRI Gateway

Interface IP-IP Gateway

Interworking with voice and video conferencing server

Service-based Charging

Call diversion

Display all registered users

Event based routing

2.3 Registrar

The registrar function handles the REGISTER messages of the Session Initiation Protocol

(SIP) for the users hosted by the SURPASS hiQ 6200 Proxy server. A REGISTER request

associates (or disassociates) a user that belongs to the supported domain with one or more

contact addresses. A contact address is any address where this user can be contacted,

including outside of the supported domain. The REGISTER message has several uses:

a) To bind a new contacting address to a user name.

b) To extend an existing contact’s TTL (Time To Live).

c) To get a list of current registered contacts.

d) To de-register in order to remove a contacting address which was bound to its name.

Before processing a REGISTER message the Registrar retrieves the User-Record from the

hiQ 30 LDAP Directory Server and performs authentication and authorization based on the

user name and password. If the user is authenticated and not blocked the registration

proceeds, otherwise the registration is rejected.

The registration procedure is usually executed when a UA becomes reachable, e.g. after the

start-up of a SIP client on a PC, the connection of a SIP phone to the IP network, or after a

change of location.



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2.4 Proxy

The proxy function of the hiQ 6200 consists of processing requests from UA’s either

responding to them or passing them on to other servers, possibly after modification.

Other clients and/or servers may be User Agents, proxy servers, redirect servers or other

servers. The proxy is not aware about the type of entity it receives the request message

from or sends the request message to. The proxy forwards (proxies) requests from clients

after it determines the destination address (location information and next hop) using the

Addressing Service.

In version 2.1 the proxy is a transaction state-full machine but not call-state-full. That

means, the proxy doesn’t supervise the session as would be required, if e.g. time based

charging were to be supported. The Proxy does store data locally about transactions and for

forking of INVITE requests.

The following basic methods are supported in version 2.1 according to IETF RFC3261 :

ACK, BYE, CANCEL, INVITE, OPTIONS, and REGISTER. The following extended methods

are also supported: INFO, PRACK, COMET, UPDATE, SUBSCRIBE, NOTIFY, MESSAGE

and REFER.

2.5 Redirect

Unlike the proxy, no SIP requests are initiated or proxied further by a SURPASS hiQ 6200

configured as a Redirect server, but rather, all SIP requests are answered with a redirect

response (3xx). The SURPASS hiQ 6200 SIP Redirect Server authenticates the request

and accesses the SURPASS hiQ 30 Directory Server using LDAP to locate the called user.

Depending on the nature of the URL, the user profile and the server configuration, a

response is created providing new contact information for reaching the called user’s user

agent and sent to the requesting user agent. The SURPASS hiQ 6200 Redirect Server is

only responsible for providing contact information to the user agent client during the SIP

session establishing phase. Registration and authorization is performed as for the SIP call

via SURPASS hiQ 6200 Proxy Server scenario.



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The Redirect function processes the same basic and extended methods as supported by

the Proxy function according to IETF RFC 3261.

2.6 Routing Capabilities

The Routing Service of the hiQ6200 SIP server supports a combination of both, time-of-day

dependent routing and server groups. As an extension of the time-of-day dependent routing

a destination address may be not only a single server address but a server group with an

assigned time window. Additionally one destination may be defined as default destination

address, selected in the case when the conditions of all other destination addresses do not

match.

The selection of the certain destination server depends on following criteria:

Time-of-Day-Dependent Routing: the destination address is chosen dependent on the

current time of day. That means, that there are up to 'm' valid destination addresses in the

routing table including a time window associated wit each.

Server Groups: the Proxy selects a certain server of a group of similar servers, which are

able to perform the same service (load sharing). A server group consists of up to 'n' similar

servers. A weighted scheduling algorithm is used. To each server a weight is assigned by

an integer value, that indicates how often this server has to be selected in comparison with

the other servers. If the weight factor is equal for all server addresses, this algorithm is

identical to a simple "round robin" algorithm.

It supports Event based routing based on the Event-header of SUBSCRIBE and PUBLISH

messages see Interface to Presence server.

2.7 Interface to the PSTN/ISDN Gateway

In version 2.0 the SIP Proxy/Redirect server has the possibility of communicating with the

Soft Switch hiQ 9200 acting as Media Gateway Controller. This enables many functions of

the MGC to be provided to SIP domain subscribers. Among other things, the hiQ 9200

provides a signaling interworking function to other protocols and with other networks. It is



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possible, for example to interwork with VoDSL subscribers, with H.323 subscribers, with

PSTN subscribers, and with other networks via SIP-T/SIP-I.

2.8 Support SIP-T/SIP-I

SIP-T/SIP-I is a mechanism to facilitate the interconnection of a PSTN network with a VoIP

network. It provides PSTN features transparency for PSTN-IP-PSTN calls. Feature

transparency is achieved by encapsulating the ISUP message received at the ingress VoIP

gateway as MIME content into an appropriate SIP message. At the egress side of the VoIP

network the ISUP information is again extracted from the SIP message and sent towards

the PSTN destination.

2.9 Switching off authentication from trusted gateways and proxies

Authentication can be switched on/off per proxy server. With authentication switched on,

each SIP request hop is authenticated first. This behavior is fine for pure SIP networks. With

the introduction of the PSTN gateway it is not necessary to authenticate SIP messages, set

up by trusted entities e.g. the hiQ 9200 controlled gateways anymore. Saving

authentications helps to increase the performance of the network. The proxy serving a hiQ

9200 controlled gateway must check whether the request is from a real known gateway or if

the request is faked by a malicious user.

2.10 Interface to the PRI Gateway

In version 2.1 the SIP Proxy/Redirect server has the possibility of communicating with the

PRI Gateway INALP IPNode 2300. The gateway allows the interworking between a SIP

domain and a classical PSTN system. The gateway is installed on PSTN side as normal

PBX. It gives a cost optimized solution for IP-TDM interworking. The gateway has a Primary

Rate Interface (2Mbit/s) for the connection to the PSTN and a LAN interface (10/100 Mbit/s)

for the connection to the SIP domain.



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2.11 Interface to presence server

The hiQ6200 is enhanced to support Presence Service with a Third-Party-Product. It

accepts subscriptions for single SIP-user for Registration Event Package and routes

SUBSCRIBE and PUBLISH messages based on the Event-header to the configured

Presence Server (new : Event based Routing Service). The realization bases on extension

of SIP :

- RFC 3265 : SIP-Specific Event Notification

- draft-ietf-sipping-reg-event-**

- draft-ietf-simple-presence-**

- draft-ietf-simple-publish-**

- draft-ietf-simple-publish-reqs-**

2.12 Interface to IP-IP Gateway

The hiQ 6200 can interwork with an 3 rd party IP-IP Gateway in a private-public scenario. The

IP-IP Gateway allows SIP based VoIP and Multimedia over IP traffic between private and

public networks. It allows a seamless integration in existing customer networks.

2.13 Interworking with voice and video conferencing server

The feature functionality for voice and video conferencing is offered by a 3 rd party vendor

and is tested with the hiQ 6200 in a SURPASS SIP scenario.

2.14 Overload Protection

With SIP V2.0 a new overload handling in combination with an Alarm Handling is

introduced. Each instance on the stack or SIP application, which detects load/overload,

informs the SIP stack to reduce the number of SIP messages to be processed. For the

detection of load/overload three administrable levels according to the alarming levels are



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introduced:

Critical > 95% consummation of a single resource

Major > 80% consummation of a single resource

Minor > 70% consummation of a single resource

Alarm clearance < 60% consummation of a single resource.

When load/overload levels are reached, the SIP stack reduces the overall load by

decreasing the number of accepted SIP requests. Additionally to the countermeasures in

the SIP stack an alarm is generated which is displayed at the NetManager. When the load is

below the certain load level, the SIP stack is informed in order to accept more requests

again and the alarm is cleared.

2.15 Service based Charging

The hiQ 6200 implements a service based charging mechanism, where an operator can

activate / deactivate per SIP method (REGISTER, INVITE, BYE,...) the generation of a

CDR. If charging is activated, e.g. for REGISTER, for each successful registration of user a

CDR in either binary AMA format or comma separated ASCII format will be generated and

stored on disk.

Retrieval of the CDR files will be via FTP.

2.16 Call Diversion

In the PSTN telephony network, redirection information is passed through the network in

ISDN/ISUP signaling messages. This information is used by various service providers and

business applications to support enhanced features for the end user. The analogous

mechanism for providing redirect information enables such enhanced features for the SIP

users. When a request is diverted in SIP the following information is lost

by whom the request was diverted

reason why the request was diverted

To prevent from this, a diversion header is added when a SIP proxy server, a SIP redirect



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server, a SIP application server or SIP user agent changes the ultimate endpoint, which will

receive the call. However the diversion information is not added for normal call routing.

When a diversion occurs, a diversion header is added to the forwarded request or forwarded

3xx response. The diversion header contains the Request-URI of the requests before the

diversion. Additionally the reason why the diversion occurred is added.



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3 Software Architecture

The SURPASS hiQ 6200 is based on a modular software architecture as shown in the picture.

Figure 3-3 hiQ 6200 software architecture

The main software components are:

a) Operating System: The SURPASS hiQ 6200 uses a standard Solaris version 8 operating

system hardened by the disabling and blocking-out of not needed interfaces and

functionality. In this way, a high degree of security against the known forms of intrusion

is achieved.

b) Unified Mediation Layer (UMLA): a software layer common to the Surpass hiQ controller

family designed to shield the upper stacks and applications from changes to the native

operating system. In this fashion, an upgrade of the hiQ to the latest version of Solaris

can be done without changes to the applications.

c) Communication Stacks: in the case of the SURPASS hiQ 6200 these comprise the

Internet Protocol (IP) stack, the Transaction Control Protocol (TCP) stack, the User Data

Protocol (UDP) stack, and the in-house developed Session Initiation Protocol (SIP)

stack.



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Solaris O/S

Unified Mediation Layer (UMLA)

Communication Stacks (SIP TCP/UDP IP)

Registrar Proxy Redirect

A&A UDS OA&M

hiQ30LDAP Server Net Manager



d) Registrar, Proxy, and Redirect functions: these provide the actual SIP session handling

functions as already described in the previous section.

e) Authorization and Authentication (A&A), and User Data Service (UDS): which provide

support services to the principal SIP session handling functions for A&A and routing.

f) Operations, Administration and Maintenance interface: provides the Graphical User

Interface (GUI) for administration via the NetManager.



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4 Hardware Architecture

The SURPASS hiQ6200 Proxy/Redirect server is based on a high performance SUN Netra

120 server using Solaris 8 operating system. The SURPASS hiQ 6200 is realized as a multi-

threaded application for optimized CPU usage.

Figure 4-4 Sun Netra 120



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5 Management

5.1 Overview

The SURPASS hiQ 6200 SIP Server and the hiQ 30 Directory server are integrated in the

SURPASS management concept. All management functions, such as administration of

subscriber data in the SURPASS hiQ 30 and configuration data in the data in the SURPASS

hiQ 6200 SIP Server, and start-up, can thus be performed by a single centralized entity, the

NetManager via JAVA application GUI. For installation of the hiQ 6200 includes an

integrated Web server.

Key features which are provided with the Operator GUI for the hiQ 6200 SIP Server are:

User Administration

Session Handling

Administration for SIP server operation as a proxy server or redirect server

Authentication

Basic configuration of the SIP server and co-located Registrar

Administration of the Registrar

Monitoring of the SIP server status, including statistics (measurements) and alarming

Routing

The new, completely Java based Operator GUI of hiQ 6200 takes full advantage of Sun's

Java Web Start technology. Java Web Start uses a Web browser for automating the whole

installation and upgrade process. It provides easy, one-click activation of the Operator GUI,

eliminating complicated installation or upgrade procedures. On each launch, Java Web Start

checks the Web server to see if a new version of the application is available, and

automatically downloads and launches it. Thus, applications are automatically brought up-

to-date without any complicated upgrade procedure.



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5.2 Security

As Java Web Start is built on top of the Java 2 platform, a comprehensive security

architecture is provided with the Operator GUI running in a restricted environment

("sandbox") with limited access to files and network.

5.3 Alarming and Statistics

Certain key values and events are monitored by the administration software, and reported

as alarms at the NetManager when they occur or they reach an administrable threshold.

Alarm messages are sent to the NetManager via Simple Network Management Protocol

(SNMP).

Statistics keeping is also a part of the management software. Some of the static and traffic

values that can be accessed any time by the operator are:

a) Number of registered SIP users

b) Number of successful/unsuccessful registrations

c) Number of successful/unsuccessful Invite

d) Number of successful/unsuccessful LDAP queries

e) Number of successful/unsuccessful authentication failures

f) Number of processed IP messages

Similarly, dynamic values like: available/used memory and processor load are logged and

can be displayed any time.



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6 Security

The SURPASS hiQ 6200 supports SIP digest authentication mechanism.

Additional overall SIP security aspects are discussed in the security document enclosed with

this offer and in the SIP architecture and services document.



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7 Technical Data

2.1 General

The SURPASS hiQ6200 Proxy/Redirect server is based on the following commercial

platform:

SUN Netra 120

UltraSPARC Iii+, Superscalar SPARC* Platform 9

650 MHz processor

4 GB Maximum memory

Dual Ethernet/Fast Ethernet, STP

Solaris 8 O/S

Apache Web Server and Tomcat Servlet Engine for OA&M support

UMLA

SIP Proxy/Redirect/Register server software

Normal operation: 5° C to 40°;

Short term 96h operation: -5° C to 50°C

7.1 Performance

SURPASS hiQ 6200 SIP Proxy with one SUN Netra 120 supports up to 60.000 BHCA in

Proxy mode, 100.000 BHCA in Redirect mode at 20.000 registered users.

7.2 Reliability

The reliability of the SURPASS hiQ 6200 is determined by the reliability of the commercial



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platform SUN Netra. In a future version of the hiQ 6200 server clustering will be offered for

additional reliability.

7.3 Compliance to Standards

The SURPASS hiQ 6200 Version 2.1 is compliant with the IETF drafts and RFC’s:

- RFC 3261: Session Initiation Protocol

- RFC 2617: HTTP Authentication: Basic and Digest Access Authentication

- RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1

- RFC 2045: Multipurpose Internet Mail Extensions

- RFC 1332: The MD5 Message-Digest Algorithm

- SIP Registration draft-schulzrinne-sip-register-00

- SIP Supported Header

- SIP-T

- SIP-T Feature Transparency for PSTN calls (RFC 3204)

- ISUP to SIP Mapping

- The SIP INFO method (RFC 2976)

- Offer/Answer model with SDP

For a complete list of standards adhered-to please see the document in this offer detailing

the SIP architecture and services.



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8 Abbreviations

BHCA Busy Hour Call AttemptsCPL Call Processing LanguageGUI Graphical User InterfaceHTML Hyper Text Markup LanguageHTTPS Hyper Text Transport Protocol (Secure)IETF Internet Engineering Task ForceIP Internet ProtocolLDAP Light-Weight Directory Access ProtocolMIME Multipurpose Internet Mail ExtensionsNNI Network to Network InterfaceOA&M Operations Administration and MaintenancePRI Primary Rate InterfaceRFC IETF Request For CommentsRRS Routing and Registration ServerSIP Session Initiation ProtocolTCP Transmission Control ProtocolTTL Time to LiveUA User AgentUDP User Datagram ProtocolUMLA Unified Mediation LayerURL Universal Resource Locator



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product hiq 6200 v2.1_hie

Documents

customer information

sip solution sip

functional description

sip registrar proxy

communication networks5

software architecture

support siptsip

ipip gateway