Cabletron Systems DMS-100 Feature packaging, DMS-Core feature packages Package Title Description

38Chapter 1: Introduction to the EIU

TCP

Each TCP connection has its own state machine. For the number of allowed connections, refer to Table 5, TCP connection limits by Supernode subsystem in this document. There are also SOS limitations in that applications that require hundreds or thousands of connections are not supported.

Internet Protocol and Internet Control Message Protocol

When an EIU goes ManB or SysB, any qualifying EIU that is available takes over. The first EIU that failed broadcasts reverse-RIP messages advertising its loss-of-connectivity to the network. In this way, the routers on the LAN that are immediately notified of the second EIU takeover.

However, there is a worse case scenario in which the reverse-RIP messages are lost on the LAN. As a result, the entry for the first EIU must time-out in the routing table in each router before these routers start sending datagrams to the second EIU. This time-out can take up to 3 min. This limitation is imposed by the RIP implementation on the EIU. A possible option is to configure the routers on the LAN to use only address resolution protocol (ARP) and not RIP to communicate with the DMS-100 switch. However, the ARP-cache time-out on the router must be set to a low value (1 min is the recommended time).

All subnet size combinations are permitted in table IPNETWRK. However, the subnet size in the DMS-100 switch must be the same as the subnet size of the LAN to which the DMS-100 switch is connected. This requirement is a result of the limitation of the RIP version 1.0 implementation in the EIU. The IP subnet must be allocated for each DMS-100 switch. Refer to “Addressing” on page 50.

Feature packaging

Feature packaging applies to software loaded on the DMS-core. In general, these packages provide the central maintenance functionality for the new remote processors and the protocol software.

Prior to CSP02, the feature packages for the software resident in the DMS-core are summarized in table 1.

Table 1 DMS-Core feature packages

Package	Title	Description
NTXF05AA	Ethernet interface unit	The is the basic package
		needed to datafill and
		maintain the EIU. No protocol
		software is included in this
		package.
(Sheet 1 of 2)

297-8991-910 Standard 03.01 August 1999