RFC 1195 OSI ISIS for IP and Dual Environments December 1990 1.5 Advantages of Using Integrated IS-IS 2 Symbols and Abbreviations 3 Subnetwork Independent Functions 3.1 Exchange of Routing Information 3.2 Hierarchical Abbreviation of IP Reachability Information 3.3 Addressing Routers in IS-IS Packets 3.4 External Links 3.5 Type of Service Routing 3.6 Multiple LSPs and SNPs 3.7 IP-Only Operation 3.8 Encapsulation 3.9 Authentication 3.10 Order of Preference of Routes / Dijkstra Computation 4 Subnetwork Dependent Functions 4.1 Link Demultiplexing 4.2 Multiple IP Addresses per Interface 4.3 LANs, Designated Routers, and Pseudonodes 4.4 Maintaining Router Adjacencies 4.5 Forwarding to Incompatible Routers 5 Structure and Encoding of PDUs 5.1 Overview of IS-IS PDUs 5.2 Overview of IP-Specific Information for IS-IS 5.3 Encoding of IP-Specific Fields in IS-IS PDUs 6 Security Considerations 7 Author's Address 8 References A Inter-Domain Routing Protocol Information A.1 Inter-Domain Information Type A.2 Encoding B Encoding of Sequence Number Packets B.1 Level 1 Complete Sequence Numbers PDU B.2 Level 2 Complete Sequence Numbers PDU B.3 Level 1 Partial Sequence Numbers PDU B.4 Level 2 Partial Sequence Numbers PDU C Dijkstra Calculation and Forwarding C.1 SPF Algorithm for IP and Dual Use C.2 Forwarding of IP packets Callon