Additions/subtractions needed? Let me know.
- Circuit Switched – created only when needed. i.e. ISDN and dial-up.
- Leased Lines – dedicated connection. TDM based.
- Packet switched – shared bandwidth using virtual circuits. i.e. Frame Relay.
- Cell Switched – ATM
- Broadband – xDSL, Cable, Wireless
Time Division Multiplexing (TDM)
- Multiple channels such as voice, video, and data can be combined
- DS1 or T1 provides 24 time slots of 64kbps each and one 8 kbps control time slot
- DLCI = L2 addressing
- LMI reports VC status.
- LMI has 3 types. Cisco, ANSI, Q.933A. Auto tries all three.
- Multipoint interfaces require L2-to-L3 address resolution. Done via inverse-ARP or static “frame-relay map”.
- Physical interface is multipoint by default. i.e Serial0/1
- Static L2-to-L3 mappings override dynamic mappings.
- “frame-relay interface-dlci <dlci #>” on point-to-point subifs. LMI does not communicate DLCI number on subifs.
- Enabled automatically when a supported protocol is cfgd. i.e. “ip address 220.127.116.11 255.255.255.0”
- Requests are sent out all circuits assigned to the interface for all supported protocols.
- Requests can be disabled via “no frame-relay inverse-arp”. Replies can not be disabled.
- Automatically supports multicast/broadcast via a replicated unicast.
- Circuit-based ring topology.
- ATM or Packet Over SONET(POS)
- Optical carrier rates. i.e. OC-1 =51.85 Mbps OC-255=13.21 Gbps