product hiq 6200 v2.1_hie
TRANSCRIPT
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Information and Communication Networks
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Product DescriptionSURPASS hiQ 6200
SIP Registrar Proxy and RedirectServer V2/V2.1
[@Project][@customer]
Information and Communication Networks
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
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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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