Multicast
Latest 10 Articles
IP multicast - good in theory, bad in practice. [EtherealMind]
Source IP address in multicast packets. [ipSpace]
Multicasting content in the twilight of social media. [Networking Nerd]
Egress anycast in Cloudflare network. [ipSpace] [Cloudflare]
IP multicast - next steps to make it real. [NANOG 79 YouTube]
DMVPN. [Russ White]
MLD - Multicast Listener Discover. [ipCisco]
CGMP. [ipCisco]
IGMP. [ipCisco]
Unicast, Broadcast, Multicast, Anycast. [ipCisco]
Older Articles
Multicast in an EVPN world. [NANOG 72 YouTube]
Create IP multicast tree graphs from operational data. [ipSpace]
DMVPN or firewall-based VPNs? [ipSpace]
Using FQDN for DMVPN hubs. [Fragmentation Needed]
Where do you want to move the complexity? [ipSpace]
Regional internet exits in large DMVPN deployment. [ipSpace]
Label switched multicast - Ethernet header. [Packet Mischief]
The future of multicast and QoS. [ipSpace]
Label Switched Multicast (LSM) -- an introduction. [Packet Mischief]
LSM configuration. [Packet Mischief]
Packet walk. [Packet Mischief]
OSPF vs EIGRP for DMVPN. [Packet Mischief]
DMVPN split default routing. [ipSpace]
DMVPN split default routing and internet access. [ipSpace]
PMTUD doesn't work with IP multicast. [ipSpace]
More PIM-BiDir considerations. [Lost In Transit]
IPv6 multicast. [Lost In Transit]
Next-generation multicast: NG-MVPN. [Lost in Transit]
HSRP-aware PIM. [Lost In Transit]
Scaling overlay virtual networking videos. [ipSpace]
Unreliable multicast means unreliable VMware VSAN. [EtherealMind]
Using EEM to speed up multicast convergence when receiver is dually connected. [Lost in Transit]
Lessons learned from deploying multicast. [Lost in Transit]
How to configure IP multicast PIM on ECMP (on Mellanox). [EtherealMind] [Mellanox]
Interdomain multicast. [Reddit]
Scaling BGP-based DMVPN networks. [ipSpace]
The fundamental difference between phase 2 and phase 3 DMVPN. [ipSpace]
Easy to follow resource for multicast. [Reddit]
IGMP and PIM in multicast VXLAN transport networks. [ipSpace]
BGP routing in DMVPN networks. [ipSpace]
IGMP snooping in IPTV. [StackExchange]
Combining DMVPN with existing MPLS/VPN network. [ipSpace]
Integrating DMVPN-based Internet VPN with MPLS/VPN WAN. [ipSpace]
RSVP over DMVPN. [ipSpace]
More private AS numbers. [ipSpace]
The impact of changed NHRP behaviour in DMVPN networks. [ipSpace]
VM-level IP multicast over VXLAN. [ipSpace]
NHRP rate limiting can hurt your DMVPN network. [ipSpace]
Migrating from a phase 1 DMVPN to a phase 2/3 network. [ipSpace]
Multiple DMVPNs on a single hub. [PacketLife]
NVGRE -- because one standard just wouldn't be enough. [IOS Hints]
OSPF-over-DMVPN using two hub routers. [IOS Hints]
DMVPN as a backup for MPLS/VPN. [IOS Hints]
Video: Auto-RP over NBMA design issues. [CCIE Blog]
More OSPF-over-DMVPN questions. [IOS Hints]
Understanding static multicast routes. [CCIE Blog]
QoS in large-scale DMVPN networks. [IOS Hints]
Spoke-to-spoke IP multicast over DMVPN? [IOS Hints]
Understanding advanced PIM shared tree designs. [CCIE Blog]
Troubleshooting multicast routing. [CCIE Blog]
PIM-SSM. [PacketLife]
IP multicast is like Banyan Vines. [IOS Hints]
RFC 5790 - lightweight IGMPv3 and MLDv2 protocols - another shot at multicast - but why? [Etherealmind]
RFC 5771: IANA guidelines for for IPv4 multicast address assignments. [IETF]
IPv4 Address Ranges
224/4 = 224.0.0.0 → 239.255.255.255
224/8 = link local only
232/8 = SSM
233/8 = GLOP
IGMP
Host to default gateway router.
IGMP Snooping on LAN switch: reduces LAN traffic.
IGMP v3: adds explicit leave.
PIM
Router to router.
PIM-SM:
explicitly builds unidirectional shared tree (rooted at the RP).
PIM-DM:
implicitly builds shortest path trees by flooding multicast traffic domain-wide and then pruning back where not needed (i.e. no receivers).
PIM-SSM:
build tree rooted at one source.
MOSPF
Extension to OSPF that allows routers to share info about group memberships.
MBGP
Extension to BGP.
Allows multicast topology info to be exchanged separately from normal unicast info.
Still relies on underlying PIM.
MSDP
Allows PIM-SM to have RP redundancy.
Allows inter-domain multicast.
Each multicast tree has an RP, and all RPs are peers.
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