WAN Technologies Based on CCNA 4 v 3

Wide-area Networks (WANs) © 2004, Cisco Systems, Inc. All rights reserved. 2

Metropolitan-Area Network (MANs) © 2004, Cisco Systems, Inc. All rights reserved. 3

Path Determination © 2004, Cisco Systems, Inc. All rights reserved. 4

Internetworking • Any internetwork must include the following: Consistent end-to-end addressing Addresses that represent network topologies Best path selection Dynamic or static routing Switching © 2004, Cisco Systems, Inc. All rights reserved. 5

Router: core of WAN technologies ©cisco • Routers send packets from one interface/network to

WAN Topology Star Topology Full-Mesh Topology Partial-Mesh Topology © 2004, Cisco Systems, Inc. All

Router Internal Components © 2004, Cisco Systems, Inc. All rights reserved. 8

Router Internal Components © 2004, Cisco Systems, Inc. All rights reserved. 9

Internal Components of a 2600 Router © 2004, Cisco Systems, Inc. All rights reserved.

External Connections on a 2600 Router © 2004, Cisco Systems, Inc. All rights reserved.

Router External Connections © 2004, Cisco Systems, Inc. All rights reserved. 12

Computer or Terminal Console Connection © 2004, Cisco Systems, Inc. All rights reserved. 13

Modem Connection to Console or Auxiliary Port © 2004, Cisco Systems, Inc. All rights

WAN Technology © 2004, Cisco Systems, Inc. All rights reserved. 15

WAN Service Providers © 2004, Cisco Systems, Inc. All rights reserved. 16

Physical Layer: WANs © 2004, Cisco Systems, Inc. All rights reserved. 17

WAN Types © 2004, Cisco Systems, Inc. All rights reserved. 18

Router Serial WAN Connectors © 2004, Cisco Systems, Inc. All rights reserved. 19

DCE Serial Connections © 2004, Cisco Systems, Inc. All rights reserved. 20

WAN Line Types and Bandwidth © 2004, Cisco Systems, Inc. All rights reserved. 21

CSU/DSU © 2004, Cisco Systems, Inc. All rights reserved. 22

Modem Transmission © 2004, Cisco Systems, Inc. All rights reserved. 23

WAN Standards © 2004, Cisco Systems, Inc. All rights reserved. 24

WAN Encapsulation © 2004, Cisco Systems, Inc. All rights reserved. 25

WAN Data-Link Protocols © 2004, Cisco Systems, Inc. All rights reserved. 26

Circuit Switching © 2004, Cisco Systems, Inc. All rights reserved. 27

Packet Switching © 2004, Cisco Systems, Inc. All rights reserved. 28

WAN Link Options © 2004, Cisco Systems, Inc. All rights reserved. 29

WAN Link Options © 2004, Cisco Systems, Inc. All rights reserved. 30

Analog Dialup © 2004, Cisco Systems, Inc. All rights reserved. 31

ISDN © 2004, Cisco Systems, Inc. All rights reserved. 32

ISDN Router with standard serial interface, connected to a terminal adapter © 2004, Cisco

Leased Line • Leased lines are not only used to provide direct point-to-point connections between Enterprise LANS, they can also be used to connect individual branches to a packet switched network. © 2004, Cisco Systems, Inc. All rights reserved. 34

WAN with X. 25 • X. 25 provides a low bit rate, shared-variable capacity

Frame Relay • Most Frame Relay connections are based on PVCs rather than SVCs. • It implements no error or flow control. This leads to reduced latency. • Frame Relay provides permanent shared medium bandwidth connectivity that carries both voice and data traffic. © 2004, Cisco Systems, Inc. All rights reserved. 36

ATM • Asynchronous Transfer Mode (ATM) is a technology capable of transferring voice, video, and data through private and public networks. • It is built on a cell based architecture rather than on a frame-based architecture. © 2004, Cisco Systems, Inc. All rights reserved. 37

DSL • DSL uses existing twisted-pair telephone lines to transport high-bandwidth data • DSL service is considered broadband, as it uses multiple frequencies within the same physical medium to transmit data © 2004, Cisco Systems, Inc. All rights reserved. 38

ADSL Technology Splitter • The local loop connects the splitter to the DSLAM • DSLAM connected to ISP using ATM technology • Voice and data use separate frequency ranges (voice 0 -4 Khz, data 20 Khx – 1 Mhz) © 2004, Cisco Systems, Inc. All rights reserved. 39

Cable Modem • Enhanced Cable Modems enable twoway. High speed data transmissions using the

Cable Data Network Architecture © 2004, Cisco Systems, Inc. All rights reserved. 41

Modern WAN © 2004, Cisco Systems, Inc. All rights reserved. 42

WANs Operate at the Lower Three Levels of the OSI Model © 2004, Cisco

Comparing WAN Traffic Types © 2004, Cisco Systems, Inc. All rights reserved. 44

Steps In WAN Design © 2004, Cisco Systems, Inc. All rights reserved. 45

Three-Layer Design Model • The links connecting the various sites in an area that provide access to the enterprise network are called the access links or access layer of the WAN. • Traffic between areas is distributed by the distribution links, and is moved onto the core links for transfer to other regions, when necessary. © 2004, Cisco Systems, Inc. All rights reserved. 46

Advantages of the Hierarchical Approach • Scalability: networks can grow without sacrificing control or manageability • Ease of Implementation: clear functionality at each layer • Ease of troubleshooting: Isolation of problems in the network is easier • Predicatability network modelling and caapacity plannng easier • Protocol Support: mixing current and future applications and protocols is easier • Manageability: all the above improve the manageability of the network © 2004, Cisco Systems, Inc. All rights reserved. 47

Internet for WAN Connectivity © 2004, Cisco Systems, Inc. All rights reserved. 48

One-Layer Hierarchy © 2004, Cisco Systems, Inc. All rights reserved. 49

Using the Internet as an Enterprise WAN • Enterprise WANs will have connections to the Internet. • This poses security problems but also provides an alternative for inter-branch traffic. • VPN technologies can solve security issues © 2004, Cisco Systems, Inc. All rights reserved. 50