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This chapter describes the uOne system hardware components and the functionality they provide as part of the uOne operations.
The uOne architecture is designed to scale from small (23 ports) to very large installation configurations. uOne can conceivably handle millions of subscribers. No matter how large the system grows, all uOne hardware and software components remain essentially the same. Hardware and software components can be replicated within the system as needed to provide the desired level and scale of services.
The gateway is a Cisco AS5300 access server with the MMoIP fax (i.e., store and forward fax) feature for fax support. Equipped with VoIP feature cards, the server can use the server's quad T1/E1 Public Switched Telephone Network (PSTN) interface and either local-area network (LAN) or wide-area network (WAN) routing capabilities to provide up to a 96/120 channel gateway for VoIP packetized voice traffic. It manages delivery of a call on a DS0 to an H.323 call or vice-versa. Once instructed which gateserver is to get a given telephone call for unified messaging services, the gateway maps that telephone call from a PRI (Primary Rate Interface) channel onto the Ethernet TCP/IP link using the H.323 or appropriate call control protocol, or vice-versa. The gateway handles the call connections to and from the telephone switching equipment and provides call information such as RDNIS (Redirected Dialed Number Identification Service), DNIS (Dialed Number Identification Service), and ANI (Answer Number Indication). For inbound calls, this information is directed to the gateserver for use by the uOne system. For outbound calls, it is useful for billing. VoIP used as a PSTN gateway leverages the standardized use of H.323-based Internet telephone client applications. More information on the store-and-forward fax feature is available at:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120limit/120xj/sf_fax
The gatekeeper acts as a monitor of all H.323 calls within its zone on the LAN. The gatekeeper is a Cisco 36xx router. The main purpose of the gatekeeper is to work in unison with other gatekeepers in a widely distributed, large-scale implementation. It provides H.323 call routing and distribution functions based on the dial plan for the implementation. It distributes phone calls based upon volume, network, and other load conditions, and performs least-cost routing. For more information on gatekeeper installation and configuration, see Configuring Voice over IP for the Cisco 3600 Series at:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/voice_c/vcprt1/vcvoip.htm
The Catalyst 2900 performs the function of Ethernet switching between the servers and routers that are part of the uOne system. This is a "low-end" hub / switching unit (10/100 Mbit, full/half duplex) that provides basic Ethernet connectivity between the various local components of the system. For a local installation, this unit provides the required data connections between the various hardware components included in the solution. In larger scale implementations, the Cisco 5000 series units, which possess much greater capabilities, are able to address much more complex issues and are more appropriate than the 2900 units. Obviously, for a widely distributed implementation, a wide-area network (WAN) is used in conjunction with this switching hub unit to meet total connectivity requirements.
It is highly recommended that all Ethernet links to this hub be 100 Mbps and full duplex. On a Catalyst 2900 series switch, you can check this via the mode button and the LEDs. Mismatches in speed and duplex can result in bulk data transmission problems. If any links do not auto negotiate 100 Mbps full duplex, you can explicitly configure it. Via IOS on a Catalyst 2900 series switch, you can configure:
interface fastethernet 0/<port>
speed 100
duplex full
or on a Solaris host using an hme driver, you can configure the /etc/system file using:
set hme:hme_adv_autoneg_cap=0
set hme:hme_adv_100hdx_cap=0
set hme:hme_adv_100fdx_cap=1
The messaging server is a Sun computer running Solaris 2.6 and Netscape Messaging Server 4.1. It acts as the message storage facility for the uOne system. Components provided by Cisco also run on this server, in conjunction with the messaging server software, to provide message arrival notification services to the appropriate gateserver.
The directory server is a Sun computer running Solaris 2.6 and Netscape Directory Server 4.0 to provide the directory services required to support the uOne system.
Release 4.2 includes paging services in support of new message notification services and SNR (Single Number Reach). Two methods of paging are supported—SMTP and SNPP. The SNPP method uses a server running Solaris 2.6, as well as the paging server software. The recommended paging server is equipped with a CentralData SCSIModemServer that houses a number of Class 2 PCMCIA modem cards in a pooled arrangement. Class 2 modems are required because Class 1 modems do not provide the proper hardware flow control capabilities. This modem pool provides shared access to the modems used to contact and communicate with the appropriate paging service providers via modem paging protocols, such as IXO/TAP.
The SCSI modem server recommended for use is a self-contained set of 8 or 16 PCMCIA slots in a 19-inch rack mountable chassis. The chassis connects to the Sun host via a single-ended SCSI 2 cable. It accepts 8 or 16 PCMCIA Type II compliant Fax/Modems. The modems are hot-swappable and receive an RJ11-type phone jack. Release 4.2 includes drivers that support the Sun Solaris operating system. You can purchase fax/modems from a wide range of vendors.
(This information can be found at the Central Data web site.)
The gateserver is made up of the following components:
Posted: Mon Sep 25 20:23:49 PDT 2000
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