1 WAN Connection Types There are three types

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WAN Connection Types There are three types of Wan Connectivity : • Dedicated Lines • Circuit Switching • Packet Switching 2

Dedicated Lines • Used for shorter to medium distances and for longer connectivity. • Private line • Bandwidth is fixed • Line is 24 hrs up • If you use it or if you don’t use it you have to pay money • eg: Leased Lines 3

Circuit Switching • Used for medium to longer distances and for shorter connectivity. • Bandwidth is fixed • Whatever you use you have to pay money for it. (Billing Depends upon the Usage) • eg: ISDN , PSTN (Dial Up connections) 4

Packet Switching • Used for medium to longer distances and for longer connectivity. • Bandwidth is shared • eg: Frame-Relay 5

Encapsulation PPP • Point to Point Protocol HDLC • High level Data link Control • Open Standard Protocol • Vendor proprietary (works with same and Protocol (works with different company same company Routers i. e. Cisco– only, i. e. Cisco-Cisco, Nortel, Cisco–Multicom. Nortel-Nortel, etc. ) • Supports Authentication • Supports Compression • No Support for Authentication • No Support for Commpression 6

PPP Authentication In PPP two types of Authentication : • PAP - Password Authentication Protocol • 2 Way Handshaking protocol • Username and password are sent in clear text • No Security • CHAP- Challenge Handshake Authentication protocol • 3 Way Handshaking protocol • Username is sent in clear text and Password in encrypted form • Secure 7

Public Switched Telephone Network • Analog Signal • Maximum Speed for 33 to 40 Kbps • Call Establishment is Slower (minimum 1 minute) • Terminated & PSTN Switch at Exchange • Supports Single services at a time. 8

Integrated Services Digital Network • Digital Signal • Minimum Speed for 128 Kbps • Call Establishment is faster (within 2 sec) • Terminated & ISDN Switch at Exchange • Supports Multiple services at a time. 9

ISDN Types • BRI – Basic Rate Interface - (2 B + 1 D) channels - Each channel 64 kbps - B channel used for data transmission - D Channel used for signaling(16 kbps) - (2* 64) + (1 * 16) = 144 kbps - B standards for Bearer - D standards for Delta 10

ISDN Types • PRI – Primary Rate Interface 2 Standards : European Standard (E 1) - 30 B + 1 D channels - (30*64) + (1*64) = 2. 048 Mbps US Standard (T 1) - 23 B + 1 D channels - (23*64) + ( 1*64) = 1. 544 Mbps 11

ISDN Connectivity ISDN SWITCH S/T Cable BRI 0 NT 1 ISDN Service Provider Network E 0 192. 168. 1. 150 PC TA Fax LAN - 192. 168. 1. 0/24 Phone 12

Dial on Demand Routing • Connection is Automated connection is established when ever a request comes to the router and disconnection is done using Idle-Timeout • All these configurations are to be made on the router • Interesting Traffic is identified using Dialer List 13

Network Address Translation • Translates Private addresses to Public and Public addresses to Private. • Allows Communication from the private world to the public world and not vice versa. • Used for internet sharing 14

ISDN for Internet Configuration • BRI interface configurations • Authentication • Dialer commands • ISDN Switch Type • NAT • Access-List • Routing Protocol • Misc. Commands • Troubleshooting commands 15