VoIP Terminology

In a VoIP-based system VoIP or IP PBX starts up (boots up) like any other servers. This can be running on a generic OS based hardware or proprietary OS and specialized server hardware. Once the booting up is complete, the IP phones and gateways can register with the call server. The IP phone and/or gateway must first access a DHCP to obtain an IP address. The DHCP may be part of the call server, or it may be a separate server. Once an IP address has been assigned, the IP device contacts the call server to register. The call server may have a common set of privileges and restrictions for IP devices or an administrator can make the feature assignments. The call server or another assigned server also adds this device and its phone number(s) to the DNS to support directory services. When a user picks up the phone to make a call, the dial tone is generated locally by the phone or by the call server. The IP device then sends one or more packets requesting a connection and the features to be implemented during the connection, such as a conference call. A permanent H.323 TCP session is established between the VoIP device (IP Phone) and the call server. This is true for most proprietary signalling protocols. SIP uses UDP for the signalling path. The call server then determines whether the other device is available or busy. If available, the call server contacts the receiving device and instructs both the caller and called devices to establish a peer-to-peer UDP path to carry the RTP speech. The call server becomes dormant during the call until one of the devices terminates the call. The "'call server then breaks the peer-to-peer connection and records the call event as part of the Call Detail Record (CDR).

VoIP Common Classes across vendors

CallManager- Provides call processing, call control, transfer, call routing functions and tons of phone features. Covers Call Server, IP PBX or soft switch implementation. Examples are: Cisco Call Manager, Avaya Communication Manager, Nortel Call Server, etc.

CallServer – covers server hosting the Call Processing Entity. It is basically a vendor proprietary OS or standard OS customized for vendor running on special or general purpose hardware.

Media Gateway – Covers VoIP Gateways, remote gateways, media gateways (Avaya) SRST (Cisco), CME (Cisco) like devices.

IP Phone – covers IP Phones

IP Phone Group – covers group of phones registered with a given call processing entity

Signaling Service – It covers H.323, SIP, Signaling Service (Nortel), SCCP (Cisco), SES (Avaya), MGCP (used in client server set up for example in gateway trying to talk to a server) and H.248 (MEGACO) used between). The H.323, and most proprietary signaling, is carried over TCP, while SIP operates over UDP.

DHCP Service – Used by IP devices such as IP Phones to get an IP address before they can register with call processing entity

Application Service – covers Voice Mail, Value added services, IP SLA, Modular Messaging, AES, Conference Service, Presence Service, SQL service,

Redundancy Group – entities such as call processing entities including IP PBX and softswitches, media gateways and certain other entities are present in pairs to provide redundancy support.

TFTP service – Using this service firmware and other upgrade on the vendor devices can be performed.

CTI service -

DNS service -


· SSC (Succession System Controller) Card (Nortel)

· VGMC (Voice Gateway Media Card) Card (Nortel)

· DLTC (Digital/Analog Line Trunk card) Card (Nortel)

· IPSI Card (Avaya)

· CLAN Card (Avaya)

· MedPro Card (Avaya)

· VoIP Engine card (Avaya)

· VAL Card (Avaya)

Network Connections:

· E-LAN (Nortel)

· T-LAN (Nortel)

· Session

Nortel Product Portfolio:
Communication & Application Servers Portfolio

Communication Server 1000

Communication Server 1000 is a server-based, full-featured IP PBX, providing the benefits of a converged network plus advanced applications and over 750 world-class telephony features. Fully distributed over IP LAN & WAN infrastructure with built-in reliability and survivability, Communication Server 1000 supports business-critical applications, including unified messaging, customer contact center, IVR, wireless VoIP and IP phones.

Key Features:

* Feature rich with over 750 call processing and telephony features * Highly scalable with support for up to 22,500 IP users off of one Call Server, multiple Call Servers networked together can support unlimited scalability * World class reliability and redundancy mechanisms - highly reliability architectural elements that maximize network uptime with extensive redundancy mechanisms to ensure network uptime including survivability options such as Campus and Geographic redundancy to support network failover * Extensive desktop portfolio includes; Wireless, Soft-phones, IP, Digital and Analog set support, to meet diverse end-user requirements * Supports business-critical applications, including IP Contact Center, CallPilot unified messaging, and integrated services such as conferencing, one-number-follow-me Personal Call Director, recorded announcement, network-wide attendant and messaging * Telephony integration with desktop application providers such as Microsoft and IBM

List of CS1K Versions:
CS1K-E 4.0
CS1K-E 4.5
CS1K-E 5.0
CS1K-M 4.0
CS1K-M 4.5
CS1K-M 5.0
CS1K-S 4.0
CS1K-S 4.5
CS1K-T 4.0
CS1K-T 4.5

Typical CS1000 deployment:

Business Communications Manager

[http://products.nortel.com/go/product_content.jsp?segId=0&parId=0&prod_id=43959 Link to Nortel Business Communication Manager (BCM)] portfolio delivers small to medium-sized businesses and branch offices an award winning converged voice and data solution, providing a choice of IP-enabled or pure-IP strategy. Leveraging existing Meridian, Norstar, and Communication Server 1000 investments, Business Communications Manager offers the features businesses of all sizes require like telephony, unified messaging, multimedia call center, interactive voice response, IP routing and data services such as firewall, wireless, and more.

Nortel BCM is an IP-enabled communication system that integrates sophisticated voice and datacapabilities, VoIP gateway functions and quality of service (QoS) data-routing features into a singlesystem for small sites, multi-sites and branch offices. Nortel BCM provides a variety of desktopcommunications options and offers a broad choice of voice and data software applications, such asUnified Messaging and Multimedia Call Center, optimized for the small-to-medium businessenvironment.

Survivable Remote Gateway (SRG)

[http://products.nortel.com/go/product_content.jsp?segId=0&parId=0&prod_id=44605 Link to Survivable Remote Gateway (SRG)] The Survivable Remote Gateway (SRG) acts as a survivable VoIP gateway that extends Communication Server 1000 features and applications to a small branch office. This provides a consistent desktop experience and enables applications across the enterprise network, plus branch survivability and e911 access in the event of a network or system failure.

The Survivable Remote Gateway is available in two versions that leverage the Business Communications Manager platforms:

* Survivable Remote Gateway 200/400 supports up to 90 Survivable IP users. * Survivable Remote Gateway 50 is a more cost-effective IP Branch Office solution for the Communication Server 1000 that supports up to 80 survivable IP users with release 2.0.

Key Features:

* Consistent user experience with simplified management * Allows distribution of trunking across WAN * Survivability * 911 support * Integrated and consistent data networking option

CallPilot Portfolio

[http://products.nortel.com/go/product_content.jsp?segId=0&parId=0&prod_id=55720 Link to CallPilot Portfolio info in Nortel] Nortel's CallPilot Unified Messaging combines voicemail, fax and e-mail into a single location that can be accessed from anywhere, whether over the Internet or by telephone. Nortel's CallPilot Unified Messaging allows your employees to be more productive and stay connected with customers and business affiliates, while reducing operating expenses.

Nortel's CallPilot Unified Messaging can be a crucial tool for today's enterprise business environment, and can help accelerate business success.

[http://products.nortel.com/go/product_content.jsp?segId=0&catId=null&parId=0&prod_id=44039&locale=en-US Link to CallPilot info in Nortel] CallPilot provides Voice/Fax Messaging as well as integrated Unified Messaging capabilities through the users’ familiar desktop e-mail environment or Web based Unified Messaging and personal mailbox management with My CallPilot. CallPilot 5.0 introduces several new features and functionalities focused on reducing total cost of ownership (TCO), improving the user experience and ease of use, increasing robustness and reliability, and providing additional messaging parity functionality to expand the addressable market.

CallPilot Mini
CallPilot Mini is a voicemail/Unified Messaging solution for small businesses using Meridian 1 Option 11C and Meridian Option 11C Mini PBX phone systems.

Messaging 100
Messaging 100 delivers a scalable and sophisticated messaging platform for small-to-medium-sized businesses that require up to 40 subscriber mailboxes and 9 hours of message storage. Applications include Call Center Basic, Unified Messaging, Networking, and an array of voice mail features.

Messaging 100/150 Basic Contact Center
Messaging 100/150 Basic Contact Center supports 20 configured agents, 2 skillsets, 20 routing steps/skillset, 30 built-in announcements, 15 lines, 2 skillset mailboxes, 20 Intelligent overflow rules/skillsets, 15 simultaneous incoming calls in the system, and all agents can be supervisors.

Messaging 150
Messaging 150 delivers a scalable and sophisticated messaging platform for small-to-medium-sized businesses that require up to 300 subscriber mailboxes and 82 hours of message storage. Applications include Call Center Basic, Unified Messaging, Centralized VM/AA, Networking, and an array of voice mail features.

Unified Messaging 2000
Nortel Unified Messaging 2000 provides unified messaging to both enterprise and carrier environments supporting up to 1 million users per system.

Signaling Server Platform Portfolio

[http://products.nortel.com/go/product_content.jsp?segId=0&parId=0&prod_id=16620&locale=en-US Link to Signaling Server Portfolio info in Nortel] Nortel's Signaling Server platform portfolio of products include the newest signaling technology, allowing customers to leverage the value of their installed systems, while introducing advanced functionality as networks grow and converge. The portfolio consists of innovative, scalable and easy-to-use products that reduce training, installation and operational costs while leveraging the value of existing installations.

Portfolio Products


BroadBand STP
BroadBand STP - a next generation SS7 signaling engine - delivers carrier-grade performance in a highly-scalable and flexible design to domestic and international wireless and wireline networks located around the world.
SS7 Router [http://products.nortel.com/go/product_content.jsp?segId=0&catId=null&parId=0&prod_id=9059&locale=en-US Link to SS7 info in Nortel]
The SS7 Router is an advanced, highly scalable SS7 signaling node providing a third generation, high-speed link concentration solution for network operators world-wide.
Universal Number Portability (NP) Master
Based on Nortel's next-generation signaling architecture, the Universal Number Portability (NP) Master delivers the flexibility to support a variety of dial-plans and country-specific portability requirements in either a standalone or integrated STP/NP configuration.
Universal Signaling Point
[http://products.nortel.com/go/product_content.jsp?segId=0&catId=null&parId=0&prod_id=52762&locale=en-US# Link to USP info in Nortel]
The Universal Signaling Point (USP) is the signaling gateway between circuit switched and packet networks.

Embedded LAN (ELAN)
The Embedded LAN (ELAN) is used as an IP managed segment for any Nortel Networks IP Telephony devices. This segment is also used to upload and download software to the IPT devices. It is recommended that the physical IP connections from this segment be 10Mbit/s half duplex and that there be limited generated broadcast traffic on this segment. This segment can be an L2/L3 segmented connection.
ITG Telephony LAN (TLAN)
The Telephony LAN (TLAN) is used for set type devices, trunks, and wireless IP gateway access. This segment is usually extended by either an L2 or L3 device onto the Customers IP LAN (CLAN). All UDP and TCP voice streams are passed to the ITG gateways on this segment. The ITG cards also acts as an H.323v2 gateway for Registration, Admission, and Status (RAS) defined functions.
Survivability LAN (SLAN)
The Survivability LAN (SLAN) provides the CSE1K Call Server with a physical Ethernet connection to communicate to up to four remote Media Gateway units via IP. The Call Server and Media Gateway are connected via an addressable IP daughterboard that resides on each unit’s Small Systems Controller (SSC) module. This connection is used to manage the connections and update information between the Call Server and the Media Gateways. Because QOS is set on each SLAN link, each Media Gateway can act in a “local” or “survivability” mode in the event the quality of the SLAN link is compromised in any form. When the link is reestablished the Call Server will update the Media Gateway using the SLAN link.


Signaling Protocols

Link to SS7 Protocol

White Papers [http://download.netiq.com/CMS/WHITEPAPER/Best%20Practices%20for%20Monitoring%20Nortel%20IP%20Telephony%20Networks.pdf Typical Nortel CS1K solution] [http://www.ihets.org/archive/progserv_arc/research_arc/pubs_arc/IPTTF2.pdf Nortel IP Telephony Deployment]

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