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1 Technical Bulletin Commercial - in - Confidence Bulletin No: 123 Date: Controlled Release of INDeX IP Networking Cassette (IPNC) With immediate effect Lucent Technologies are pleased to announce the controlled release of the IP Networking Cassette. The IP Networking Cassette provides a wide range of facilities and can support many applications, both at a single site and at dispersed locations, providing fast flexible Internet access, implementing e-commerce strategies, Remote Access Solutions and Voice over IP. The IP Networking Cassette Voice-over-IP solution can fully utilise all of the available bandwidth, providing significant line rental savings. It utilises voice compression techniques to optimise speech quality against cost and has up to 20 compressed voice channels with echo suppression, to G / G.729a standards. The IP Networking Cassette is designed to provide a custom solution that is both easy to use and easy to manage. Configuration of the cassette is achieved through a windows based manager program. Support of the IP networking cassette is only available with INDeX level 9 software. Level 9 software is also able to support multiple IP Networking Cassettes within the same INDeX system. Feature Overview The IP Networking Cassette supports the following standard features: TCP/IP Dynamic Host Configuration Protocol PPP, Multi-Link PPP V.120, V.110 Bandwidth Allocation Control Protocol Stac and MPPC compression PAP and CHAP Authentication Security Network Address Translation WAN port, X21,V35 or V.24 auto sensing interface Secure Firewall Remote Access Software for dial in users Time Profiles Service Quotas Page 1 of 8

2 In addition the IP Networking Cassette also supports the following optional features: V90 modems the IP Networking cassette can be supplied with 4 V90 modems Voice Over IP supports a maximum of 20 compressed voice calls NOTE: Neither of these are field upgradable options. Software Functionality TCP/IP TCP/IP has been deployed on virtually every type of hardware and software platform available today and forms the backbone of the Internet. As a result, this popular protocol suite has become the standard for achieving multivendor internetworking applications. NOTE: The IP Networking cassette does not support any version of RIP, all IP routes are administered manually. If RIP functionality is required then the Data Router Cassette should be used. Dynamic Host Configuration Protocol (DHCP) DHCP is a defined framework for providing PC s on a TCP/IP network with configuration data, specifically with IP addresses, from an administered system, for example, a Microsoft Windows NT server. Clients (hosts requiring configuration) make broadcast requests for information and Servers (hosts that manage and deliver configuration data) offer or deliver the information back to the client. The IP Networking Cassette can be configured to act as a DHCP server or client, can use a static IP address and can also be setup to allocate IP addresses to dial in users. PPP, Multi-Link PPP Point to Point Protocol (PPP), a product of the Internet Engineering Task Force (IETF), is the de facto WAN link protocol for connecting clients and servers and for interconnecting routers to form enterprise networks. PPP's main advantage is that unlike other protocols that operate at the data link layer, PPP achieves interoperability between devices by negotiating different configuration options, including link quality, link authentication, and network protocols. The IP Networking Cassette also supports Multi-link PPP, an extension to the PPP protocol that allows multiple physical connections between two points to be combined into a single logical connection. The combined connections, called a bundle, provide greater bandwidth than a single connection. Unlike channel bonding, which usually combines two channels for the duration of a connection, Multi-link PPP supports dynamic bandwidth allocation, which means that physical links can be added or removed from the bundle as needed. V.110, V.120 V Protocol set to Asynchronous PPP, a special rate adaptation scheme for ISDN. The call is presented to the local ISDN Exchange as a "Data Call". This will run at 9600 bps. It is ideal for GSM mobile phones and some bulletin boards. V Protocol set to Asynchronous PPP, a special rate adaptation scheme for ISDN. The call is presented to the local ISDN Exchange as a "Data Call". This will run at speeds of upto 64K per channel but has a slightly higher protocol overhead than pure 64K operation. Useful for some bulletin board systems as it allows the destination to run at a different asynchronous speed to the calling end. Page 2 of 8

3 Bandwidth Allocation Control Protocol (BACP) BACP provides a flexible and effective way to add and remove bandwidth between two Routers. The BACP protocol negotiates pre-defined options during the first part of a valid call. BACP is the only standards based mechanism available which allows the platform that did not initiate the call to negotiate more (or less) bandwidth with the initiator. Regardless of which end requests the extra bandwidth, it is the originator of the initial call that makes the additional calls and consequently incurs all the cost. BACP also uses a mechanism known as Bandwidth Allocation Protocol (BAP), this is responsible for the negotiations to co-ordinate the requests for adding or removing bandwidth. Hardware Compression Standards: CCP, STAC and MPPC Compression Control Protocol (CCP)---A protocol that provides a defined method of negotiating data compression over the Point-to-Point Protocol. Stacker compression (STAC)---A data compression algorithm developed by STAC Electronics that is based on the LZ compression algorithm. Microsoft Point-to-Point Compression (MPPC) is a scheme used to compress Point-to-Point Protocol packets between the IP networking Cassette and Microsoft client devices. PAP and CHAP Authentication Security Password Authentication Protocol (PAP) uses passwords to validate devices over a PPP link and to respond to authentication requests from other devices. PAP is an effective way of ensuring that only communications from authorised devices are accepted over a PPP link. PAP transmits a password in clear text, anyone who has a device for monitoring network traffic can look at it. Challenge Handshake Authentication Protocol (CHAP) can be chosen as an alternative to PAP to validate devices over a PPP link before communications are permitted. CHAP is a more secure authentication protocol than PAP as CHAP never actually transmits the password over the link. CHAP therefore defeats any attempts to obtain the password by monitoring the PPP link. Network Address Translation (NAT) Network Address Translation is a method for translating an internal IP address or network into a single globally unique IP address. There are several benefits for using NAT: internal address reuse, use of unregistered addresses, the ability to hide internal network addresses, not needing to re-address the internal network when connecting to the internet or a corporate network. A useful side effect of this feature is that many Internet Service Providers (ISP s) charge based on the number of addresses that they allocate to an account. In some cases, using a single IP number could reduce a bill by as much as 90%! This also helps to enhance the level of security within the Network by hiding its internal addressing structure. WAN port, X21,V35 or V24 auto sensing interface The IP Networking Cassette provides a WAN port for connection of X21, V35 or V24 leased lines. Being externally clocked, the IP Networking Cassette will operate at the leased line speed subscribed to. This could be upto 2048kpbs. Page 3 of 8

4 Secure Firewall Internet security concerns are addressed through the provision of an integrated firewall. This removes the need for an expensive, standalone, software solution tying up another PC. The firewall access software will allow you to control who can access external resources, and when, whilst isolating your private networks from the Internet. Firewall profiles include predefined filters for IP protocols and Services that are shown in the table below. Additional profiles can be created to support filtering on other criteria of the IP packet Amongst the protocols that can be managed in this way are: FTP Telnet SMTP Time DNS Gopher Finger HTTP POP3 NNTP SNMP IRC PPTP File Transfer Protocol. A TCP/IP application used for transferring files from one system to another. Remote Terminal Login. Used for remote access for diagnostic purposes. Simple Mail Transfer Protocol. An application. Time update protocol. Used to take the time of day from the Internet. Domain Name Server. Translates names to IP Addresses. The predecessor of HTTP. An application that, given an address, can be used to obtain information about users currently logged on to a host system. Hypertext Transfer Protocol. The part of the TCP/IP protocol suite that transmits web pa ges over the Internet. Post Office Protocol 3. The TCP/IP standard for mail transmission between server and client, POP3 is the current version. Network News Transfer Protocol. Used to set up local Internet news groups. Simple Network Management Protocol. The part of the TCP/IP protocol suite that deals with the transmission of network information for system administration and monitoring. Internet Relay Chat. A real-time, multi-user chat application. Point to Point Tunnelling Protocol. Used to establish a Virtual Private Network (VPN) over the Internet. Remote Access Server A Remote Access Server (RAS) is used to support dial-in services. Service access can be either from ISDN or by modem. Time Profiles Time Profiles can be used to stipulate when a Service or User's Dial In facility are operational. This is a particularly powerful feature when used in conjunction with some of the other features of the IP Networking Cassette, such as CLI checking and the firewall. For example a home worker accessing the network can be configured so that they will only be allowed on to the network if they dial in from their home telephone number during normal working hours. Once on the network the firewall can restrict them to only accessing the file server and only allow the use of file transfer protocols. Conversely, a member of the IT department could be allowed access to the network without restriction 365 days of the year providing they are calling from a trusted telephone number. Service Quotas Quotas are associated with outgoing calls where they place a time limit on calls to a particular Service. This avoids excessive ISDN call charges when perhaps something changes on your network (new software or hardware) and call frequency increases unintentionally. It is also a way of governing how much a certain service can be used, such as Internet Access. Once the quota is used up then the service will no longer be available. The quota time is defined in minutes and can be refreshed daily, weekly or monthly. Page 4 of 8

5 Voice Over IP Voice-over-IP (VoIP), the most talked about example of packetised voice, is real, useable and is starting to be implemented now. The ideal target environment for this technology is in the remote Branch Office. A fixed digital circuit will probably be in place already for data traffic, VoIP allows this link to be utilised for voice traffic between two sites, typically the branch and regional/head office, thereby integrating voice and data over a single link. Voice compression technology alongside support for voice prioritisation and/or Quality of Service (QoS) helps to ensure that speech quality is maintained. Just think of this service as voice-networking in the same manner as you would when using AC- 15 or DPNSS circuits - the only difference is that the fixed digital circuit carries voice and data traffic and they re terminated at each site by a router or VoIP gateway. The voice circuits are then passed on to the PBX. However, if you re using a switched service, such as PSTN or ISDN between sites, rather then a fixed circuit, then VoIP, isn t so attractive. Also if you re not going to send voice and data down the same switched circuit, then the process of packetising, or wrapping voice traffic within IP packets just causes unnecessary overheads and end-to-end delays. Due to the random nature of the Internet, it can take seconds to download the home page of your favourite web site during some periods of the day, while at others it can take minutes, or even time-out altogether due to the sheer volume of Internet traffic. NOTE: Due to this indeterminate nature that voice-over-the-internet care must be taken when considering the internet as the carrier service for VoIP. The IPNCs Voice-over-IP (VoIP) technology enables a data network to carry voice traffic along with data. Support of compression, Quality of Service (QoS) and echo cancellation technology ensures that speech quality is optimised. Each IPNC is capable of compressing 20 simultaneous calls using a choice of industry standard algorithms. The bandwidth required for VoIP must cater for both the digitised speech and the overhead resulting from the dividing the digitised speech into packets for transmission. VoIP calls have a header overhead of 28 bytes per packet, which increases the normal 12 byte Ethernet Header on a LAN to 40 bytes and the normal 7 bytes header to 35 bytes on a WAN link that is using Point to Point protocol (PPP). This equates to a 175%-200% overhead on a 20-byte voice packet! Additionally, on low speed links, data packets (e.g., 1500 byte IP packets) can delay voice packets and cause an unacceptable degradation to speech quality. It is vital to use a Quality of Service (QoS) technique. The IPNC uses the industry standard DiffServe quality of service mechanism to prioritise voice packets, fragment large packets and provide VoIP header compression to minimise the overhead from about 35 bytes for a 20-byte payload (175% overhead) to 6 bytes (30% overhead). The combination of these techniques minimises speech latency. Overheads must be taken into account when calculating the link capacity required to support voice traffic. For example, an IPNC 8kbps compression voice channel actually needs bandwidth to support 10.4 KBPS. Page 5 of 8

6 Voice Compression Modes The following list defines the available compression algorithms that can be used on any Voice call made through the IP Networking Cassette: G.711 ALAW 64K Each voice call is converted from analogue to digital (refer to G.732) and uncompressed. G.729(a) 8K A fully compliant, real-time implementation of the ITU-T fixed-point conjugatestructure, algebraic code-excited linear prediction (CS_ACELP) speech coding CS-ACELP algorithm. The CS-ACELP operates at 8kbps. The coder processes 10 msec frames of speech sampled at an 8 khz rate, which together with a 5 msec look-ahead results in a total algorithmic delay of 15 msec. For each frame of 80 samples of 16-bit linear PCM data, the coder outputs five 16-bit words. Applications using the G.729 vocoder include digital telephony, satellite and wireless communications, and Voice over G K3 MP-MLQ Frame Relay (VoFR). A real-time implementation of the ITU-T Multi-Pulse Maximum Likelihood Quantization (MP-MLQ) 6.4 KBPS and Algebraic Codebook Excited Linear Prediction (ACELP) 5.3 KBPS speech coding algorithms. The G speech coder operates upon 30 ms frame of digitised, telephone bandwidth speech signals sampled at 8 khz. The frames are divided into four 7.5 ms subframes of 60 samples each. Each frame of 240 input samples is converted into bit word of compressed data at the high rate or bit words of compressed data at the low rate The Voice Activity Detection/Comfort Noise Generation (VAD/CNG) specified in Annex A to ITU-T G is fully implemented, and may be used to further reduce the average bit rate. NetCoder 8K Each voice call is compressed using AudioCode's NetCoder Compression technique. G.726 ADPCM 32K Each voice call is compressed using the standard ADPCM compression technique (refer to G.732). This algorithm uses 32,000 bits per second. G.726 ADPCM 16K Each voice call is compressed using the standard ADPCM compression technique (refer to G.732). This algorithm uses 16,000 bits per second. NOTE: Although VoIP can be implemented on any of the INDeX s lines, quality of service can only be associated with X21, V35 and LAN traffic. If a requirement for compressed voice calls over dialup circuits such as ISDN and DPNSS it is strongly recommended that the solution offered by the Voice Compression Cassette (VCC) is used instead. Known Issues The following are known bugs that are outstanding with this release of IPNC software: 1) Cassette slot locked LED does not operate correctly - Cassette shows solid red LED instead of flashing. The following are known issues or limitations with this release of IPNC software, as such the following conditions should be observed when installing this product: 1) Where remote dial-up is to be configured from an NT4 PC, a DNS address must be specified in the dial-up networking properties. If NT4 attempts to obtain a DNS address from the IPNC, and it does not have one programmed, then the dial-up connection will fail. 2) If using ISDN backup for a WAN interface it should be noted that the WAN channel is always seen as 64kbps irrespective of both the WAN port speed configuration and the external clock speed of the interface. This should be taken into consideration if setting bandwidth management to use more than one channel. 3) During the IPNC boot-up POST diagnostics tests both red and the green status LED s will remain lit until the unit becomes fully operational, at which point the red light will be extinguished. 4) The IPNC uses Sequence check mode for STACLZ compression. This should be taken into account when connecting to another router that may be set to use Extended check mode. Page 6 of 8

7 5) The use of a firewall configuration with VOIP links is not recommended in this release 6) ICMP Messages are not supported. For this reason indication of WAN link failures are only available via SNMP. 7) On a VPN line group directed to a PC software telephone (i.e. NetMeeting) the IPNC requires a short code configuration in order to access the INDeX line group. This short code should be configured to Dial Speech. This will be documented in the next release of the manual. 8) The IPNC Installation Wizard uses an Ethernet broadcast to automatically detect any units on the LAN. These broadcasts are not normally relayed by routers or switches and a network error may be generated (TFTP Error File Not Found) by the Installation Wizard if the IPNC is not on the same LAN segment. Simply ignore this error and continue using the wizard. The following points should also be noted with respect to VOIP configuration: 1) Although Voice packets are prioritised over data, Voice signalling packets are not, for this reason on busy networks there may be a delay in signalling. I.e. Destination phone may not actually ring until the 3 rd ring tone heard by the caller. If the bandwidth considerations shown in the table below are observed this should be the worst case scenario. 2) If the system is set up to translate required extension numbers to the IPNC group, busy tones are not supported as yet on VoIP calls. I.e. if the destination is busy the caller will receive NU tone and Nobody in Group on the display. This will also be the case if all the Voice channels (configured in VPN line configuration) are busy. Busy tones are supported if the system is configured to translate numbers to individual IPNC channels. 3) When calling extensions using VOIP, which may be diverting on no answer to Voic , the ring timer on the IPNC channels should be changed from 10 seconds to something more appropriate such as 60 seconds. This can be done by changing the ring timer on any INDeX terminal and copying that terminals record to the IPNC channels. 4) In order to support DTMF tones being sent across a VOIP link the IPNC channels should be configured as MF Receivers. 5) If remote trunks are to be used across VoIP (breakout) it will be necessary to set up a number of translations within the ARS to support different dialled digit lengths. Only strings of known lengths can currently be sent to the IPNC. e.g. To dial ARS should be set to wait for all 12 digits before being sent to the IPNC. 6) Please refer to the table below to determine the number of simultaneous calls for a given bandwidth for VoIP. Speed G729.1 (8k) NetCoder (8k) G.723 (6.4k) ADPCM (32k) G.711 (64k) Transparent (64K) 56K x x 64K x x 128K K M LAN Page 7 of 8

8 Cassette Variants The IP Networking Cassette is available in four variants: IPNC : Suitable for Internet Access only solutions IPNC\-M : Suitable for Internet Access and Remote LAN Access (includes four V.90 modems) IPNC\-VC : Suitable for Internet Access and Voice over IP solutions (includes support for twenty compressed voice calls) IPNC\-M\-VC: Suitable for Internet Access, Voice over IP and Remote Access (includes four V.90 modems and support for twenty compressed voice calls). All IPNC variants support 2 simultaneous calls (two 64K channels) as standard, where a greater number of channels are required an optional INDeX licence Key (LIC-IPNC32) is required providing the maximum 32 simultaneous calls (thirty two 64K Channels) Each IPNC is supplied with a LAN Cable and Administration software on CD (CD-IPNC-ADMIN) containing: Installation Wizard for easy initial configuration of system and Internet parameters. Upgrade Wizard for upgrading operating software. The Manager - for configuration and administration of the system and its features, both voice and data. The Monitor - to display an on-line, time-stamped log of all call processing events, for all calls or selectively. An electronic manual. Training and Accreditation For further information on training and accreditation please refer to Reseller Update 254. Issued by: Mark Gibson Tel: Fax: magibson@lucent.com Internet: Page 8 of 8