1 multicastaddresslocationprotocol multicast address discovery protocol ietf vancouver – oct 2005
TRANSCRIPT
1MulticastAddressLocationProtocol
Multicast AddressDiscovery Protocol
IETF Vancouver – Oct 2005
222MulticastAddressLocationProtocol
Problem
• Enterprise Networks wish to deploy Scoped Zones.– Allows them to limit the scope of applications.• Examples: Norton Ghost, Altiris
– Many applications use “fixed” addresses.• Often due to need for (near) zero-configuration operation.
• Some haven’t even bothered to register with IANA!!Some haven’t even bothered to register with IANA!!– Address Assignment by “Atmospheric Extraction”.
– Scope range maintenance becomes complex• Must make exceptions for these “rogue” applications.
• More and more such applications popping up.
– Need a way to achieve (near) zero-configuration and yet give network admin control of addresses used by apps.
333MulticastAddressLocationProtocol
RFC 2365LocalScope
RFC 2365Local ScopeExpansion
RFC 2365Org.-LocalExpansion
239.255.0.0
239.196.0.0
239.255.255.255
239.0.0.0
RFC 2365Org-Local
Scope
239.192.0.0
RFC 2365 – Administratively Scoped Zones
• Defines only 2 Well-Known Scopes–Organization-Local Scope (239.192/14)
• Largest scope within the Enterprise network.
– Local Scope (239.255/16)
• Smallest possible scope within the Enterprise network.
–Other scopes may be equal to but not smaller in scope.
–Both scopes have expansion space below their range.
(Not to scale.)
Unassigned
239.255.253.0
444MulticastAddressLocationProtocol
Scope Relative Addresses – RFC 2365
Last
OctetOffset Description
.255 0 SAP Session Announcement Protocol (SDR)
.254 1 MADCAP Protocol
.253 2 SLPv2 Protocol
.252 3 MZAP Protocol
.251 4 Multicast Discovery of DNS Services
.250 5 SSDP
.249 6 DHCPv4
.248 7 AAP
.247 8 MBUS
9 - 255 Unassigned
Top 256 Addresses of every Admin. Scope Range.
555MulticastAddressLocationProtocol
Scope Relative – Local Scope
239.255.255.255
239.255.0.0
Local ScopeScope Relative
239.255.255.0
Local Scope
239.254.255.255
239.0.0.0
(Not to scale.)
Address Description
239.255.255.255 SAP Session Announcement Protocol (SDR)
239.255.255.254 MADCAP Protocol
239.255.255.253 SLPv2 Protocol
239.255.255.252 MZAP Protocol
239.255.255.251 Multicast Discovery of DNS Services
239.255.255.250 SSDP
239.255.255.249 DHCPv4
239.255.255.248 AAP
239.255.255.247 MBUS
666MulticastAddressLocationProtocol
Scope Relative – Org-Local Scope
239.195.255.255
239.192.0.0
Org-Local Scope Relative
239.195.255.0
Org-Local Scope
239.195.254.255
239.0.0.0
(Not to scale.)
Address Description
239.195.255.255 SAP Session Announcement Protocol (SDR)
239.195.255.254 MADCAP Protocol
239.195.255.253 SLPv2 Protocol
239.195.255.252 MZAP Protocol
239.195.255.251 Multicast Discovery of DNS Services
239.195.255.250 SSDP
239.195.255.249 DHCPv4
239.195.255.248 AAP
239.195.255.247 MBUS
777MulticastAddressLocationProtocol
Administratively-Scoped Zone Example
• ACME Enterprises:–Three levels of internal scopes •Campus Scope
•Region Scope
•Org-Local Scope– aka Enterprise-Wide Scope
–One external scope•Global scope
• i.e. everything else (Internet)
888MulticastAddressLocationProtocol
ACME’s Scoped Zones
ASIAPAC North
America
Core
EMEA
Canada East Coast US
West CoastUS
NorthRegion
EasternRegion
South Region
India
Japan
Australia
China
Internet
999MulticastAddressLocationProtocol
ACME’s Scoped Zones
ASIAPAC North
America
Core
EMEA
Canada East Coast US
West CoastUS
NorthRegion
EasternRegion
South Region
India
Japan
Australia
China
Internet
• Campus Scope: 239.190.x.x/16
Campus Scope
101010MulticastAddressLocationProtocol
ACME’s Scoped Zones
ASIAPAC North
America
Core
EMEA
Canada East Coast US
West CoastUS
NorthRegion
EasternRegion
South Region
India
Japan
Australia
China
Internet
• Regional Scope : 239.191.x.x/16
RP
RP
RP
Regional Scope
111111MulticastAddressLocationProtocol
ACME’s Scoped Zones
ASIAPAC North
America
Core
EMEA
Canada East Coast US
West CoastUS
NorthRegion
EasternRegion
South Region
India
Japan
Australia
China
Internet
• Enterprise Scope: 239.192.x.x/14
– i.e. Org-Local Scope
Enterprise Scope
121212MulticastAddressLocationProtocol
ACME’s Scoped Zones
ASIAPAC North
America
Core
EMEA
Canada East Coast US
West CoastUS
NorthRegion
EasternRegion
South Region
India
Japan
Australia
China
Internet
• Global Scope: 224.0.1.x – 238.255.255.255
Global (Internet) Scope
131313MulticastAddressLocationProtocol
RFC 2365Organization-Local Scope
RFC 2365Organization-Local Scope
ACME’s Address Assignments
• Enterprise scope = RFC 2365 Org-Local
• Keep Local scope separate.–Avoids moving applications when smaller
scopes are added later.
• Lots of other ways to assign this space.
RFC 2365LocalScope
239.255.0.0
239.196.0.0
239.255.255.255
239.0.0.0
RegionScope (/16)
CampusScope (/16)
EnterpriseScope (/14)
239.192.0.0
239.191.0.0
239.190.0.0
141414MulticastAddressLocationProtocol
Solution
•Multicast Address Discovery Protocol–Very light-weight
–Assumes no support infrastructure other than:• IP Multicast
•RFC 2365 Administratively Scoped Zones– Well-Known Scopes (Local & Org. Local Scopes)
– Scope Relative Addresses
–Runs entirely in Application Clients and Servers
151515MulticastAddressLocationProtocol
MADP Basics
• Uses a single Scope Relative Address
• Clients send Queries on this address– Request info on what multicast address(es)
application “X” is using.
– Initial Queries sent in the Local Scope.
– If no response, then queries the Org-Local Scope.
• Servers listen on these addresses.– When a Request is received, they check to see if they are
the Server for application “X”.
– If so, they send a Response containing multicast address information.• Address information was preconfigured by network admin.