Multicast

Mengenai Multicast ada beberapa jenis multicast di dunia networking.

Dense Mode

Pada dense mode, router akan mengirimkan/membanjiri trafik multicast ke semua router yang mengaktifkan multicast pada interfacenya.

Jika ada router yang tidak memiliki client yang menginginkan traffic multicast, maka router akan mengirimkan konfirmasi (prune message) agar tidak dikirimi untuk multicast lagi.

Sparse Mode

Pada sparse mode, host harus mengirimkan request terlebih dahulu, baru kemudian akan dikirimi traffic multicast.

Dala sparse mode ada router yang dipilih menjadi RP (Rendezvous Point) sebagai pusat untuk menghubungkan antara multicast source dan router-router yang memiliki host multicast user/client di bawahnya.

Pemilihan RP ada 3 :

1. Static RP
2. Auto-RP (cisco proprietary)
3. BSR

Pada IPv6 hanya ada sparse mode, tidak ada dense mode. Oleh karenanya tidak memungkinkan adanya auto-RP karena auto-RP juga membutuhkan dense-mode untuk kebutuhan pemilihan candidate RP dan Mapping Agent nya.

Untuk lebih mengetahui mengenai sparse mode dan dense mode ini, kita akan mempraktekkannya di lab dengan menggunakan GNS3.

 

• Sparse Dense Mode – Auto Mode

R1#sh ip pim rp mapping
PIM Group-to-RP Mappings
This system is an RP (Auto-RP)
This system is an RP-mapping agent

Group(s) 224.0.0.0/4
RP 1.1.1.1 (?), v2v1
Info source: 1.1.1.1 (?), elected via Auto-RP
Uptime: 00:00:05, expires: 00:02:51
R1# ]
R1(config)#ip pim send-r
R1(config)#ip pim send-rp-ann
R1(config)#ip pim send-rp-announce lo0
% Incomplete command.

R1(config)#ip pim send-rp-announce lo0 sco 255
R1(config)#ip pim send
R1(config)#ip pim send-rp-dis
R1(config)#ip pim send-rp-discovery sco 255
R1(config)#exit
R1#sh i

PIM Group-to-RP Mappings

Group(s) 224.0.0.0/4
RP 1.1.1.1 (?), v2v1
Info source: 12.12.12.1 (?), elected via Auto-RP
Uptime: 00:03:20, expires: 00:02:34
R2#
R2

PIM Group-to-RP Mappings

Group(s) 224.0.0.0/4
RP 1.1.1.1 (?), v2v1
Info source: 12.12.12.1 (?), elected via Auto-RP
Uptime: 00:03:20, expires: 00:02:34

 

• Sparse Mode – Static RP

konfig R2

!
interface Loopback0
ip address 2.2.2.2 255.255.255.255
ip pim sparse-mode
ip ospf 1 area 0
!
interface FastEthernet0/0
ip address 12.12.12.2 255.255.255.0
ip pim sparse-mode
ip ospf 1 area 0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 23.23.23.2 255.255.255.0
ip pim sparse-mode
ip ospf 1 area 0
duplex auto
speed auto
!
router ospf 1
log-adjacency-changes
!
ip forward-protocol nd
!
!
ip http server
no ip http secure-server
ip pim rp-address 2.2.2.2
!
!
!
!
!

Konfig R3

!
ip multicast-routing
!
interface Loopback0
ip address 3.3.3.3 255.255.255.255
ip pim sparse-mode
ip ospf 1 area 0
!
interface FastEthernet0/0
ip address 23.23.23.3 255.255.255.0
ip pim sparse-mode
ip ospf 1 area 0
duplex auto
speed auto
!
!
router ospf 1
log-adjacency-changes
!
no ip http secure-server
ip pim rp-address 2.2.2.2

R1#show ip pim int

Address          Interface                Ver/   Nbr    Query  DR     DR
Mode   Count  Intvl  Prior
12.12.12.1       FastEthernet0/0          v2/S   1      30     1      12.12.12.2
1.1.1.1          Loopback0                v2/S   0      30     1      1.1.1.1
R1#

R1#sh ip pim rp mapping
PIM Group-to-RP Mappings

Group(s): 224.0.0.0/4, Static
RP: 2.2.2.2

R1#
utgoing interface flags: H – Hardware switched, A – Assert winner
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 239.0.0.1), 00:47:15/00:02:59, RP 2.2.2.2, flags: SJCL
Incoming interface: FastEthernet0/0, RPF nbr 12.12.12.2
Outgoing interface list:
Loopback0, Forward/Sparse, 00:47:15/00:02:59

(*, 239.0.0.2), 00:47:15/00:02:54, RP 2.2.2.2, flags: SJCL
Incoming interface: FastEthernet0/0, RPF nbr 12.12.12.2
Outgoing interface list:
Loopback0, Forward/Sparse, 00:47:15/00:02:54

(*, 224.0.1.40), 00:57:03/00:02:59, RP 2.2.2.2, flags: SJPCL
Incoming interface: FastEthernet0/0, RPF nbr 12.12.12.2
Outgoing interface list: Null

R2#sh ip pim int

Address          Interface                Ver/   Nbr    Query  DR     DR
Mode   Count  Intvl  Prior
12.12.12.2       FastEthernet0/0          v2/S   1      30     1      12.12.12.2
23.23.23.2       FastEthernet0/1          v2/S   1      30     1      23.23.23.3
2.2.2.2          Loopback0                v2/S   0      30     1      2.2.2.2
R2#

R3#ping 239.0.0.1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 239.0.0.1, timeout is 2 seconds:

Reply to request 0 from 12.12.12.1, 60 ms
Reply to request 0 from 12.12.12.1, 60 ms
R3#sh ip mroute
IP Multicast Routing Table
Flags: D – Dense, S – Sparse, B – Bidir Group, s – SSM Group, C – Connected,
L – Local, P – Pruned, R – RP-bit set, F – Register flag,
T – SPT-bit set, J – Join SPT, M – MSDP created entry,
X – Proxy Join Timer Running, A – Candidate for MSDP Advertisement,
U – URD, I – Received Source Specific Host Report,
Z – Multicast Tunnel, z – MDT-data group sender,
Y – Joined MDT-data group, y – Sending to MDT-data group
Outgoing interface flags: H – Hardware switched, A – Assert winner
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 239.0.0.1), 00:00:26/stopped, RP 2.2.2.2, flags: SPF
Incoming interface: FastEthernet0/0, RPF nbr 23.23.23.2
Outgoing interface list: Null

(3.3.3.3, 239.0.0.1), 00:00:26/00:03:10, flags: FT
Incoming interface: Loopback0, RPF nbr 0.0.0.0, Registering
Outgoing interface list:
FastEthernet0/0, Forward/Sparse, 00:00:26/00:03:03

(23.23.23.3, 239.0.0.1), 00:00:26/00:02:40, flags: PFT
Incoming interface: FastEthernet0/0, RPF nbr 0.0.0.0
Outgoing interface list: Null

(*, 224.0.1.40), 00:58:48/00:02:28, RP 2.2.2.2, flags: SJPCL
Incoming interface: FastEthernet0/0, RPF nbr 23.23.23.2
Outgoing interface list: Null

• Dense Mode

konfig R1
!

ip multicast-routing

interface Loopback0
ip address 1.1.1.1 255.255.255.255
ip pim dense-mode
ip igmp join-group 239.0.0.1
ip igmp join-group 239.0.0.2
ip ospf 1 area 0
!
interface FastEthernet0/0
ip address 12.12.12.1 255.255.255.0
ip pim dense-mode
ip ospf 1 area 0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
router ospf 1
log-adjacency-changes

Konfig R2

ip multicast-routing
interface Loopback0
ip address 2.2.2.2 255.255.255.255
ip pim dense-mode
ip ospf 1 area 0
!
interface FastEthernet0/0
ip address 12.12.12.2 255.255.255.0
ip pim dense-mode
ip ospf 1 area 0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 23.23.23.2 255.255.255.0
ip pim dense-mode
ip ospf 1 area 0
duplex auto
speed auto
!
router ospf 1
log-adjacency-changes
!

konfig R3

!
!
ip multicast-routing

interface Loopback0
ip address 3.3.3.3 255.255.255.255
ip pim dense-mode
ip ospf 1 area 0
!
interface FastEthernet0/0
ip address 23.23.23.3 255.255.255.0
ip pim dense-mode
ip ospf 1 area 0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
router ospf 1
log-adjacency-changes
!

R3#ping 239.0.0.1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 239.0.0.1, timeout is 2 seconds:

Reply to request 0 from 12.12.12.1, 72 ms
Reply to request 0 from 12.12.12.1, 76 ms
R3#ping 239.0.0.2

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 239.0.0.2, timeout is 2 seconds:

Reply to request 0 from 12.12.12.1, 44 ms
Reply to request 0 from 12.12.12.1, 48 ms