1. Traffic Measurement and Modeling in IP multicast Wenbo Liu Wenbo Liu Communication Laboratory, HUT Supervistor : Seppo J Halme Supervistor : Seppo J Halme Instructor: Tapani Nieminen

2. Content  Background Information Mutlticast, Unicast, Broadcast IGMP, Mbone, Multicast Routing Protocols  Practical Task IP Mulitast traffic measurement, observation and modeling

3. Multicast

4. Multicast Vs Broadcast,Unicast   At multicast, one host sending packet to multiple selected destination (group of hosts). -Class D (224.0.0.0 ~ 239.255.255.255) -Point-to-multipoint. -Join or leave multicast group anytime, anywhere. -Probably hosts may belong to various kinds of network type.

5.  Unicast is one source host sending packet to one destination host. -Point-to-point.-Non-real-time. -Best-effort-delivery service of IP.  At B roadcast, a host transmitting a packet to all attached hosts.  Even simpler than unicast for the application to implement

6. IGMP  Use IGMP message to join Multicast group  Internet Group Management Protocol  It allows hosts to communicate their desired group memberships to their local router memberships to their local router  The Internet Group Management Protocol (IGMP) is used by IPv4 system(hosts and routers) to report their IP multicast group memberships to any neighboring multicast router  IGMP v1 is defined RFC1112  IGMP v2 is defined RFC2236  IGMP v3 is defined RFC2933  IP Datagram: IP hearder (20 Bytes) + IGMP Message (8 Bytes)

7. Mbone  Internet Multicast Backbone  Mbone is a virtual network, it is layered on top of part of the physical Internet to support routing of IP multicast packet.  Virtual point-to-point links is called ’Tunnels’  With Mbone, a single packet can have multiple desinations

8. Multicast Routing Protocols Dense ModeSparse Mode Distance Vector Link StateShared Tree DVMRPPIM-DMMOSPFPIM-SMCBT Multicast Routing Protocols  DVMRP- Distance Vector Multicast Routing Protocol PIM-DM- Protocol Independent Multicast, Desnse Mode  MOSPF- Multicast Open Shorest Path First  PIM-SM- Protocol Independent Multicastt Sparse ModeCBT-Core Based Tree

9. Interoperability and Delivery   Interoperability between existing unicast and emerging multicast-capable routers.   Interoperability between the various approaches to multicast routing.   Data-driven Muliticast, Broadcast and prune strategy. Send data untill the destination do not want to get more. .  Demand-driven Multicast, Router joins to forwarding tree before datagrams has transfered to destination finished already in its network.

10. Measurement, Observations of IP multicast  The basic measurement of IP multicast is generated between Otaverkko and Funet.  Tcpdump program, SDR softwre are used during this task.  Tcpdump is a network-monitoring program, that can dump traffic on the network.  Case Study: Resource: tilt-gw.mediapoli.fi Destination: OSPF-ALL.MCAST.net or other destination multicast host. other destination multicast host.

11. 16:35:39.942243 tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: S 1228941:1228941(0) win 8192 (DF) 16:35:39.944205 alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: 1592521346:1592521346(0) ack 1228942 win 33580 (DF)5:39.944333 tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet:. ack 1 win 8760 (DF) 16:35:39.990352 alpha.hut.fi.3907 > tilt-mc2.mediapoli.com.auth: S 1592585746:1592585746(0) win 32768 (DF) 16:35:39.990439 tilt-mc2.mediapoli.com.auth > alpha.hut.fi.3907: R 0:0(0) ack 1592585747 win 0 16:35:40.101776 alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: P 1:16(15) ack 1 win 33580 (DF) [tos 0x10] 16:35:40.102057 tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 1:4(3) ack 16 win 8745 (DF) 16:35:40.114484 0:0:1d:b0:16:ce 1:0:1d:0:0:0 81fd 75: 0003 0002 28f4 1000 0000 0000 0000 0000 0003 0002 28f4 1000 0000 0000 0000 0000 0000 0000 0000 0000 04d4 4400 9e00 001d 0000 0000 0000 0000 04d4 4400 9e00 001d b016 b800 0000 1700 001d 0000 0000 0000 b016 b800 0000 1700 001d 0000 0000 0000 0000 0404 0605 0000 0000 2f00 00 0000 0404 0605 0000 0000 2f00 00 16:35:40.191026 alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924:. ack 4 win 33580 (DF) [tos 0x10] 16:35:40.191134 tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 4:16(12) ack 16 win 8745 (DF) 16:35:40.192613 alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: P 16:22(6) ack 16 win 33580 (DF) [tos 0x10] 16:35:40.192838 tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 16:27(11) ack 22 win 8739 (DF) 16:35:40.225127 alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: P 22:37(15) ack 27 win 33580 (DF) [tos 0x10] 16:35:40.225342 tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 27:30(3) ack 37 win 8724 (DF) 16:35:40.364739 tilt-mc2.mediapoli.com.netbios_ns > tltnt10.hut.fi.netbios_ns: udp 50 16:35:40.389791 alpha.hut.fi.telnet > tilt- mc2.mediapoli.com.1924:. ack 30 win 33580 (DF ) [tos 0x10]

13. IP Mulitcast Application –SDR software  SDR is session direction tool, which means that it lists session to be multicast on the Mbone rather than programmers broadcast on radio and TV  At SDR, the subscriber can creat session join existing one and choose some parameters.  This tool choose free Multicast addresses and ports