Transcript WAN Connection Types

WAN Networking Protocols
WAN Connection Types
•Point-to-Point connection
•No setup before transmission
•Up to 45Mbs
•Setup before transmission
•Dial-up modems or ISDN
•Low bandwidth
•Share bandwidth
•Frame Relay and X.25
•56Kbps to 2.048Mps
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WAN Networking Protocols
High-Level Data-Link Control Protocol
• HDLC specifies an encapsulation method
for data on synchronous serial data links
using frame characters and checksums.
• Default encapsulation used by CISCO.
• Everyone has its own proprietary HDLC.
• If your are connecting a CISCO router
with another type router, you must
specify an encapsulation type (protocol).
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WAN Networking Protocols
PPP
• PPP is an Internet standard protocol to provide
point-to-point, router-to-router, and host-to-host
connections.
• It supports network layer protocols
– IP
– Novell IPX
– Apple Talk
• It can be used over several different physical
interfaces
– Asynchronous serial
– ISDN synchronous serial
– High-speed Serial Interface
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WAN Networking Protocols
Establishing PPP Communication
• Communication process is established in
three steps:
– Link Establishment
– Authentication
• Password Authentication (PAP)
• Challenge Authentication Protocol (CHAP)
– Network Layer Protocol negotiation
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WAN Networking Protocols
Link Establishment and LCP
• Link Control Protocol (LCP) is responsible
to configure and test the link.
• LCP packets can contain many different
pieces of information such as:
– Authentication
– Link Quality Monitoring and Magic Number
– Compression
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WAN Networking Protocols
Configuring PPP on Cisco Routers
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WAN Networking Protocols
Frame Relay
CSU/DSU (channel service unit/
digital service unit)
• Frame Relay provides connection-oriented, Data Link
layer communication via virtual circuits.
• ANSI defines Frame Relay as a connection between the
data terminal equipment (DTE) and the data
communication equipment (DCE) over high speed digital
medium.
• CSU/DSU is located at customer location and used for
encoding, filtering, and translating communication to
and from the digital line.
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WAN Networking Protocols
Frame Relay
• Supports many protocols, IP, Novell IPX,
Decnet, AppleTalk, ....
• Efficient and fast (56Kps to 44.736Mbps)
since it does not perform error checking.
• Uses both permanent virtual circuits (PVC)
and switched virtual circuits (SPC).
• Virtual circuits are maintained by a
software and multiplexed on onto physical
channels.
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WAN Networking Protocols
Data Link Connection Identifiers (DLCI)
• Frame Relay virtual circuits are identified by DLCIs.
• IP address need to be mapped DLCI
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WAN Networking Protocols
How Frame Relay works
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WAN Networking Protocols
Subinterfaces
• You can have multiple virtual circuits on a
single interface and treat each one as a
separate interface.
R(config)>interface s0
R(config-if)>encapsulation frame-relay [ietf]
R(config-if)>int s0.16 point-to-point (or multipoint)
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WAN Networking Protocols
Mapping Frame Relay
Manual Mapping
R(config)>interface s0
R(config-if)>encapsulation frame-relay
R(config-if)>int s0.16 multipoint
R(config-subif)>no inverse-arp
R(config-subif)>ip address 172.16.30.1 255.255.255.0
R(config-subif)>frame-relay map 172.16.30.17 16 ietf broadcast
R(config-subif)>frame-relay map 172.16.30.18 17 broadcast
R(config-subif)>frame-relay map 172.16.30.19 18
Using Reverse-ARP
R(config)>interface s0.16
R(config-subif)>encapsulation frame-relay ietf
R(config-subif)>ip address 172.16.30.1 255.255.255.0
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WAN Networking Protocols
Integrated Services Digital Network (ISDN)
• ISDN is a digital service designed to run
over existing telephone networks.
• ISDN supports both voice, video, and data
• Call setup is faster than with a modem.
• Data rates are faster than one modem
connection.
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WAN Networking Protocols
ISDN Components
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WAN Networking Protocols
ISND Terminals
• Terminal adapter: A converter device that allows
non-ISDN devices to operate on an ISDN
network.
• Terminal Equipment 1 (TE1): A device that
supports ISDN standards.
• Terminal Equipment 2 (TE2): A non-ISDN
device.
• Network Termination 1 (NT1): A device that is
attached to ISND BRI lines to provide power. It
also terminates the 2-wire connection from CO
and connects to the 4-wire customer network.
• Network Termination 2 (NT2): A provider
equipment.
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WAN Networking Protocols
Reference Points
• U
– The U-interface is the actual two-wire cable which connects
the customer’s equipment to the telecommunications provider
• R
– The R-interface is the wire or circuit that connects TE2 to the
TA
• S
– The S-interface is a four-wire cable from TE1 or TA to the
NT1 or NT2
• T
– The point between NT1 and NT2, which is also called the Tinterface
• S/T
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WAN Networking Protocols
Connecting to the Provider
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WAN Networking Protocols
ISDN Switch Types
• Interfaces
– Basic Rate Interface (BRI)
– Primary Rate (Interface)
• Potential Switch Types To Be Obtained from
ISDN Providers
– basic-5ess, basic-dms100, basic-ni,....
• Service Profile Identifiers (SPIDs)
– Reference number assigned to ISDN channels
• Functions like a phone number
– Frequently referred to as ISDN phone numbers
– Most modern ISDN systems now have a feature
called AutoSPID
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WAN Networking Protocols
ISDN with CISCO Router
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