PIM Hello
在 PIM Hello 中，携带多项 PIM 协议报文参数，主要用于 PIM Neighbor 间的 PIM 协议报文的控制。
具体如下：
1）DR_Priority：表示各路由器接口竞选DR的优先级，优先级越高越容易获胜。
2）Holdtime：表示保持邻居为可达状态的超时时间。如果在超时时间内没有收到PIM邻居发送的Hello报文，路由器则认为邻居不可达。
3）LAN_Delay：表示共享网段内传输 Prune 报文的延迟时间。
4）Neighbor-Tracking：表示邻居跟踪功能。
5）Override-Interval：表示 Hello 报文中携带的否决剪枝的时间间隔。
Frame 2: 76 bytes on wire (608 bits), 76 bytes captured (608 bits) on interface -, id 0
Ethernet II, Src: HuaweiTe_3e:77:c4 (00:e0:fc:3e:77:c4), Dst: IPv4mcast_0d (01:00:5e:00:00:0d)
Internet Protocol Version 4, Src: 10.0.45.5, Dst: 224.0.0.13
Protocol Independent Multicast
0010 .... = Version: 2
.... 0000 = Type: Hello (0)
Reserved byte(s): 00
Checksum: 0x2720 [correct]
[Checksum Status: Good]
PIM Options: 5
Option 1: Hold Time: 105
Option 19: DR Priority: 1
Option 20: Generation ID: 3401703534
Option 2: LAN Prune Delay: T = 0, Propagation Delay = 500ms, Override Interval = 2500ms
Option 21: State-Refresh: Version = 1, Interval = 60s
PIM Assert
Frame 34: 60 bytes on wire (480 bits), 60 bytes captured (480 bits) on interface -, id 0
Ethernet II, Src: HuaweiTe_1b:76:bc (00:e0:fc:1b:76:bc), Dst: IPv4mcast_0d (01:00:5e:00:00:0d)
Internet Protocol Version 4, Src: 10.0.45.3, Dst: 224.0.0.13
Protocol Independent Multicast
0010 .... = Version: 2
.... 0101 = Type: Assert (5)
Reserved byte(s): 00
Checksum: 0x2633 [correct]
[Checksum Status: Good]
PIM Options
Group: 239.1.1.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
0... .... = Bidirectional PIM: Not set
.000 000. = Reserved: 0x00
.... ...0 = Admin Scope Zone: Not set
Masklen: 32
Group: 239.1.1.1
Source: 192.168.2.1
Address Family: IPv4 (1)
Encoding Type: Native (0)
Unicast: 192.168.2.1
0... .... = RP Tree: False
.000 0000 0000 0000 0000 0000 0000 0000 = Metric Preference: 0
Metric: 0
PIM Join / PIM Prune
Frame 48: 68 bytes on wire (544 bits), 68 bytes captured (544 bits) on interface -, id 0
Ethernet II, Src: HuaweiTe_54:69:ea (00:e0:fc:54:69:ea), Dst: IPv4mcast_0d (01:00:5e:00:00:0d)
Internet Protocol Version 4, Src: 10.0.45.4, Dst: 224.0.0.13
Protocol Independent Multicast
0010 .... = Version: 2
.... 0011 = Type: Join/Prune (3)
Reserved byte(s): 00
Checksum: 0xef3b [correct]
[Checksum Status: Good]
PIM Options
Upstream-neighbor: 10.0.45.3
Address Family: IPv4 (1)
Encoding Type: Native (0)
Unicast: 10.0.45.3
Reserved byte(s): 00
Num Groups: 1
Holdtime: 210
Group 0
Group 0: 239.1.1.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
0... .... = Bidirectional PIM: Not set
.000 000. = Reserved: 0x00
.... ...0 = Admin Scope Zone: Not set
Masklen: 32
Group: 239.1.1.1
Num Joins: 0
Num Prunes: 1
IP address: 192.168.2.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
0000 0... = Reserved: 0x00
.... .0.. = Sparse: Not set
.... ..0. = WildCard: Not set
.... ...0 = Rendezvous Point Tree: Not set
Masklen: 32
Source: 192.168.2.1
PIM State-Refresh
Frame 34: 70 bytes on wire (560 bits), 70 bytes captured (560 bits) on interface -, id 0
Ethernet II, Src: HuaweiTe_54:69:e9 (00:e0:fc:54:69:e9), Dst: IPv4mcast_0d (01:00:5e:00:00:0d)
Internet Protocol Version 4, Src: 10.0.46.4, Dst: 224.0.0.13
Protocol Independent Multicast
0010 .... = Version: 2
.... 1001 = Type: State-Refresh (9)
Reserved byte(s): 00
Checksum: 0x30e9 [correct]
[Checksum Status: Good]
PIM Options
Group: 239.1.1.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
Masklen: 32
Group: 239.1.1.1
Source: 192.168.2.1
Address Family: IPv4 (1)
Encoding Type: Native (0)
Unicast: 192.168.2.1
Originator: 10.0.45.3
Address Family: IPv4 (1)
Encoding Type: Native (0)
Unicast: 10.0.45.3
0... .... = RP Tree: False
.000 0000 0000 0000 0000 0000 0000 1010 = Metric Preference: 10
Metric: 2
Masklen: 24
TTL: 254
1... .... = Prune indicator: Set
.0.. .... = Prune now: Not set
..1. .... = Assert override: Set
Interval: 60
PIM Graft
Frame 77: 68 bytes on wire (544 bits), 68 bytes captured (544 bits) on interface -, id 0
Ethernet II, Src: HuaweiTe_4e:66:64 (00:e0:fc:4e:66:64), Dst: HuaweiTe_54:69:e9 (00:e0:fc:54:69:e9)
Internet Protocol Version 4, Src: 10.0.46.6, Dst: 10.0.46.4
Protocol Independent Multicast
0010 .... = Version: 2
.... 0110 = Type: Graft (6)
Reserved byte(s): 00
Checksum: 0xec0c [correct]
[Checksum Status: Good]
PIM Options
Upstream-neighbor: 10.0.46.4
Address Family: IPv4 (1)
Encoding Type: Native (0)
Unicast: 10.0.46.4
Reserved byte(s): 00
Num Groups: 1
Holdtime: 0
Group 0
Group 0: 239.1.1.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
Masklen: 32
Group: 239.1.1.1
Num Joins: 1
IP address: 192.168.2.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
Masklen: 32
Source: 192.168.2.1
Num Prunes: 0
PIM Graft-Ack
Frame 78: 68 bytes on wire (544 bits), 68 bytes captured (544 bits) on interface -, id 0
Ethernet II, Src: HuaweiTe_54:69:e9 (00:e0:fc:54:69:e9), Dst: HuaweiTe_4e:66:64 (00:e0:fc:4e:66:64)
Internet Protocol Version 4, Src: 10.0.46.4, Dst: 10.0.46.6
Protocol Independent Multicast
0010 .... = Version: 2
.... 0111 = Type: Graft-Ack (7)
Reserved byte(s): 00
Checksum: 0xeb0a [correct]
[Checksum Status: Good]
PIM Options
Upstream-neighbor: 10.0.46.6
Address Family: IPv4 (1)
Encoding Type: Native (0)
Unicast: 10.0.46.6
Reserved byte(s): 00
Num Groups: 1
Holdtime: 0
Group 0
Group 0: 239.1.1.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
Masklen: 32
Group: 239.1.1.1
Num Joins: 1
IP address: 192.168.2.1/32
Address Family: IPv4 (1)
Encoding Type: Native (0)
Flags: 0x00
Masklen: 32
Source: 192.168.2.1
Num Prunes: 0