Chapter 2: EIU messaging protocols 61DMS-100 Family EIU User Guide TELECOM12router is determined based on the simple load balancing rules and the status ofthe router.IP ScreeningPackets destined for the Supernode can be screened at the IP level. If thesource of the packet is determined to be invalid, the packet is dropped by theEIU. For more information, refer to data schema table EXNDINV in thisdocument.Protocol engineeringThis section provides information on engineering rules and data for each of theprotocol layers. It also contains discussions on the maintenance of the protocolstack and its performance.IP throttlingIP throttle engineering is required to control congestion in the DS30 links. Ifthe IP throttle is not properly engineered, the robustness of the LMS on whichEIUs are located is compromised. This situation occurs because of thepotentially large number of datagrams transferred between EIUs andSuperNode nodes across LMS.IP (as a network layer protocol that transfers datagrams between EIUs and theSuperNode nodes) does not have built-in flow control mechanism to providethrottling. As a result, manual control is required. Table IPTHRON assertsmanual control over IP throttling of datagrams transmitted over DS30 links.For information on table IPTHRON, refer to “Chapter 3: EIU datafill”. Formore information on IP throttling, refer to “IP throttling” on page 65.For information on EIU provisioning rules for LPP, SSLPP, and SNSE-LIS,refer to Provisioning Rules for LPP, SSLPP, and SNSE LIS, SystemEngineering Bulletin number 92-02-001, version 01.09.TCP connection managementThe TCP layer provides reliable delivery of the data to its remote peer throughwell-defined connections. The connection management for SuperNode TCP ishandled through datafill in table IPHOST. Table IPHOST permits theoperating company to vary the number of TCP connections on a per nodebasis.When changing this value, note the following points:• decreasing the allowed number of connections causes all connections to bedropped• existing connections are maintained when you increase the number ofconnections
