Wenbo Liu. Supervistor : Seppo J Halme Instructor: Tapani Nieminen

Transcription

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

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

3 Multicast Co mputer Co mputer Com puter M Multicast Group Ad dress Co mpu ter

4 Multicast Vs Broadcast,Unicast At multicast, one host sending packet to multiple selected destination (group of hosts). -Class D ( ~ ) -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 Broadcast, 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 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 Multicast Subnet A Router IP Tunnel Router Multicast Subnet B is layered on top of part of the physical Internet to support routing of IP multicast packet. IP Tunnel Router Router IP Tunnel IP Tunnel Router Virtual point-to-point links is called Tunnels Router Router Router With Mbone, a single packet can have multiple desinations Multicast Subnet C Multicast Subnet D

8 Multicast Routing Protocols Multicast Routing Protocols Dense Mode Sparse Mode Distance Vector Link State Shared Tree DVMRP PIM-DM MOSPF PIM-SM CBT 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 Mode CBT-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.

11 16:35: tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: S : (0) win 8192 <mss 1460> (DF) 16:35: alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: : (0) ack win <mss 1460> (DF)5: tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet:. ack 1 win 8760 (DF) 16:35: alpha.hut.fi.3907 > tilt-mc2.mediapoli.com.auth: S : (0) win <mss 1460,nop,wscale 0> (DF) 16:35: tilt-mc2.mediapoli.com.auth > alpha.hut.fi.3907: R 0:0(0) ack win 0 16:35: alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: P 1:16(15) ack 1 win (DF) [tos 0x10] 16:35: tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 1:4(3) ack 16 win 8745 (DF) 16:35: :0:1d:b0:16:ce 1:0:1d:0:0:0 81fd 75: f d e00 001d b016 b d f :35: alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924:. ack 4 win (DF) [tos 0x10] 16:35: tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 4:16(12) ack 16 win 8745 (DF) 16:35: alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: P 16:22(6) ack 16 win (DF) [tos 0x10] 16:35: tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 16:27(11) ack 22 win 8739 (DF) 16:35: alpha.hut.fi.telnet > tilt-mc2.mediapoli.com.1924: P 22:37(15) ack 27 win (DF) [tos 0x10] 16:35: tilt-mc2.mediapoli.com.1924 > alpha.hut.fi.telnet: P 27:30(3) ack 37 win 8724 (DF) 16:35: tilt-mc2.mediapoli.com.netbios_ns > tltnt10.hut.fi.netbios_ns: udp 50 16:35: alpha.hut.fi.telnet > tiltmc2.mediapoli.com.1924:. ack 30 win (DF ) [tos 0x10]

12 08:56: > : udp 2 08:56: > : igmp query [ttl 1 08:56: > : P : (20) ack win (DF) [t 0x10] 08:56: > : igmp nreport [ttl 1 08:56: > :. ack 20 win 8500 (DF 08:56: > : OSPFv2-hello 44: rtrid backbone dr [tos 0xc0] [t 1] 08:56: > : udp 24 08:56: > : icmp: host unreachabl 08:56: > : icmp: host unreachabl 08:56: > : icmp: host unreachabl 08:56: > : icmp: host unreachabl 08:56: > : icmp: host unreachabl 08:56: > : igmp nreport [ttl 1 08:56: > : icmp: host unreachabl 08:56: > : icmp: host unreachabl 08:56: > : icmp: host unreachabl 08:56: > : udp 33 08:56: > : udp 68 08:56: > : icmp: host unreachabl 08:56: > : icmp: host unreachabl 08:56: > : igmp nreport [ttl1 08:56: > : udp 28 08:56: > : udp 28 08:56: > : udp 24 08:56: > : udp 24 08:56: > : udp 33 08:56: > : udp 2 08:56: > : udp 47 08:56: > : igmp nreport [ttl1 08:56: > : OSPFv2-hello 44: rtrid backbone dr [tos 0xc0] [t 1]!XGS

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

14 Respons e tim e to SYN R equest titl-gw.mediap oli.fi to o sp f-all.mcast.n et ( )

15 Response time to SYN Request titl-gw.mediapoli.fi to ospf-all.mcast.net ( )

16 Response time to SYN Request titl-gw.mediapoli.fi to ospf-all.mcast.net