IP Routing Configuration in a Router with Troubleshooting

Transcription

1 International Journal of Electronics and Computer Science Engineering 93 Available Online at ISSN IP Routing Configuration in a Router with Troubleshooting 1 Gyan Prakash Pal, 2 Sadhana Pal, 3 Aradhana Jyotsana, 4 Satya Prakash 1 SIT, Meerut, 2 VIET, Greater Noida (U.P.), 3 Allahabad University, 4 VBS University Abstract- Today whole world is connected via internet for worldwide communication. Different network devices like router, switch, bridge, hub, server, multiplexer/demultiplexer and modem are used for communication. To connect different networks only routers are used to provide routes for packets of data from one network to another. To communicate between different networks, IP routing is must. This paper helps you to configure IP routing and bring-up an interface of a router and also troubleshoot the network connectivity between IP devices. In this paper CLI commands are used for configuration. Keywords: Routers, IP addresses, CLI commands. I. INTRODUCTION Routers are network layer devices; the network layer manages the device addressing and search the location of devices on the network to determine the best way to send data between devices that are not locally attached. Routers break up a broadcast domain, by default. Routers use logical addressing to provide packet switching and packet filtering by using an access list. When routers connect two or more networks together and use logical addressing (IPv4 or IPv6) is called internetwork. Routers use a routing table to make path selection and to forward packets to remote networks. When a packet is received on a router interface, the destination IP address is checked. If the destination IP address is not present in the same network, it will look up the destination network address in the routing table. Once the router chooses an exit interface, the packet will sent to that interface and sent out in the local network. If the router cannot find an address of the packet s destination network in the routing table, the router drops the packet. Two types of packets are used at the Network layer: Data Packets: Protocols used to support data traffic are called routed protocols; examples of routed protocols are IP and IPv6. Route update packets: Protocols that send route update packets are called routing protocols; examples of some common ones are RIP, RIPv2, EIGRP and OSPF. Route update packets are used to help build and maintain routing tables on each router. An example of a routing table is shown in figure (1). The routing table used in a router includes the following information:

2 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al E0 S0 S0 E Network Routing Table Inter face E S0 0 Metric Network Routing Table Inter face S S S E0 0 Figure1. Routing table used in a router Network Address: A router must maintain a routing table for individual routing protocols. it uses 32 bit network address to specify the port in a network. Interface: The exit interface which destined for a specific network. Metric: The distance to the remote network. Different routing protocols use different ways of computing this distance. The routing protocol RIP uses hop count (the number of routers a packet passes through a route to a remote network) for metric. Some other routing protocols use bandwidth, delay of the line and load for metric count. Metric II. CONFIGURING IP ROUTING We are going to configure a real network. Figure (2) shows three routers on different locations as Delhi, Mumbai and Chennai. You can give router name on the basis of location (or your choice); in this network same is used.

3 IP Routing Configuration in a Router with Troubleshooting Figure 2 Configuring IP routing Cisco 2800 Series routers are used in above figure. Command Line Interface (CLI) is used to configure the routers. Table 1 show the IP addresses, which are used to configure IP routing. Each network in the following table has a 24 bit subnet mask ( ) as a default mask for class B network. Table 1 Network Addressing for the IP Network Router Network Address Interface Address Delhi S0/2/ Delhi F0/ Delhi F0/ Mumbai S0/2/ Mumbai S0/2/ Mumbai F0/ Mumbai F0/ Chennai S0/0/ Chennai F0/ Chennai F0/ The router configuration is really a pretty straightforward process since you just need to add IP address to your interfaces and then perform a no shutdown on those same interfaces.

4 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al. 96 III. DELHI ROUTER CONFIGURATION You need to configure three interfaces to configure the Delhi router. Configure the host name of each router will make identification much easier. Also configure interface description, banner and router password. It s really good to make a habit of configuring these commands on every router. To get started, I performed an erase startup-configuration on the router and reloaded, so we will start in setup mode. I choose NO to enter setup mode, which will get us straight to the user-name prompt of the console, and configure with the help of CLI. Router#erase startup-config Erasing the nvram filesystem will remove all configuration files! Continue? [confirm] [OK] Erase of nvram: complete %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram Router#reload Proceed with reload? [confirm] %SYS-5-RELOAD: Reload requested by console. Reload Reason: Reload Command. System Bootstrap, Version 12.1(3r)T2, RELEASE SOFTWARE (fc1) Copyright (c) 2000 by cisco Systems, Inc. cisco 2811 (MPC860) processor (revision 0x200) with 60416K/5120K bytes of memory Self decompressing the image : ########################################################################## [OK] Restricted Rights Legend Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c) of the Commercial Computer Software - Restricted Rights clause at FAR sec and subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS sec cisco Systems, Inc. 170 West Tasman Drive San Jose, California Cisco IOS Software, 2800 Software (C2800NM-IPBASE-M), Version 12.3(14)T7, RELEASE SOFTWARE (fc2) cisco 2811 (MPC860) processor (revision 0x200) with 60416K/5120K bytes of memory Processor board ID JAD05190MTZ ( ) M860 processor: part number 0, mask FastEthernet/IEEE interface(s) 8 Low-speed serial(sync/async) network interface(s) 239K bytes of non-volatile configuration memory K bytes of processor board System flash (Read/Write) Cisco IOS Software, 2800 Software (C2800NM-IPBASE-M), Version 12.3(14)T7, RELEASE SOFTWARE (fc2) Technical Support: Copyright (c) by Cisco Systems, Inc.

5 IP Routing Configuration in a Router with Troubleshooting Compiled Wed 22-Mar-06 18:40 by pt_team --- System Configuration Dialog --- Continue with configuration dialog? [yes/no]: no Press RETURN to get started! Router>en Router# Now you are in privileged-mode and configure the router. Router#config terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)#hostname Delhi Delhi(config)#enable secret Sana Delhi(config)#banner motd # Enter TEXT message. End with the character '#'. It's Gyan Prakash & Sadhana Company. If you are not an authorized person immedia tly Logout from the network. Thanks, Have a Nice Day. # Delhi(config)# Delhi(config)#interface serial0/2/0 Delhi(config-if)#ip address Delhi(config-if)#description WAN Connection to Mumbai Router. Delhi(config-if)#no shutdown %LINK-5-CHANGED: Interface Serial0/2/0, changed state to down Delhi(config-if)#interface fastethernet 0/0 Delhi(config-if)#ip address Delhi(config-if)#description LAN Connection to PC0. Delhi(config-if)#no shutdown %LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up Delhi(config-if)#interface fastethernet 0/1 Delhi(config-if)#ip address Delhi(config-if)#description LAN Connection to PC1. Delhi(config-if)#no shutdown %LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up Delhi(config-if)#line console 0 Delhi(config-line)#password Sana Delhi(config-line)#login Delhi(config)#line vty 0?

6 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al. 98 <1-15> Last Line number <cr> Delhi(config)#line vty 0 15 Delhi(config-line)#password Sana Delhi(config-line)#login Delhi(config-line)#exit Delhi(config)#^Z %SYS-5-CONFIG_I: Configured from console by console Delhi#copy running-config startup-config Destination filename [startup-config]? Building configuration... [OK] Delhi# To view the IP routing table created on a Cisco router, use the command show ip route. The command output is shown as follows: Delhi#sh ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic downloaded static route Gateway of last resort is not set /24 is subnetted, 2 subnets C is directly connected, FastEthernet0/0 C is directly connected, FastEthernet0/1 Delhi# It s important to remember that only configured, directly connected networks are going to show up in the routing table. That s why only Fast Ethernet 0/0 and Fast Ethernet 0/1 are showing up. You can see the serial interfaces come up when the other side of the serial links will be operational. Delhi#config t Enter configuration commands, one per line. End with CNTL/Z. Delhi(config)#interface serial 0/2/0 Delhi(config-if)#bandwidth? < > Bandwidth in kilobits Delhi(config-if)#bandwidth 64

7 IP Routing Configuration in a Router with Troubleshooting Delhi(config-if)#^Z %SYS-5-CONFIG_I: Configured from console by console Delhi#sh controllers serial 0/2/0 Interface Serial0/2/0 Hardware is PowerQUICC MPC860 DTE V.35 TX and RX clocks detected IV. MUMBAI ROUTER CONFIGURATION First we erase the startup-configuration and reload the router. Router>en Router#erase startup-config Erasing the nvram filesystem will remove all configuration files! Continue? [confirm] [OK] Erase of nvram: complete %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram Router#reload Proceed with reload? [confirm][enter] [Outputs cut] --- System Configuration Dialog --- Continue with configuration dialog? [yes/no]: no Press RETURN to get started! Router>en Router# Now we can start to configure the router. Router#config terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)#hostname Mumbai Mumbai(config)#enable secret Sana Mumbai(config)#interface serial0/2/0 Mumbai(config-if)#ip address Mumbai(config-if)#description WAN Connection to Delhi Router. Mumbai(config-if)#no shutdown %LINK-5-CHANGED: Interface Serial0/2/0, changed state to up Mumbai(config-if)#interface serial0/2/1 Mumbai(config-if)#ip address Mumbai(config-if)#description WAN Connection to Chennai Router. Mumbai(config-if)#no shutdown %LINK-5-CHANGED: Interface Serial0/2/1, changed state to down

8 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al. 100 Mumbai(config-if)#interface fastethernet 0/0 Mumbai(config-if)#ip address Mumbai(config-if)#description LAN Connection to PC2. Mumbai(config-if)#no shutdown %LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up Mumbai(config-if)#interface fastethernet 0/1 Mumbai(config-if)#ip address Mumbai(config-if)#description LAN Connection to PC3. Mumbai(config-if)#no shutdown %LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up Mumbai(config-if)#line console 0 Mumbai(config-line)#password Sana Mumbai(config-line)#login Mumbai(config)#line vty 0? <1-15> Last Line number <cr> Mumbai(config)#line vty 0 15 Mumbai(config-line)#password Sana Mumbai(config-line)#login Mumbai(config-line)#exit Mumbai(config)#banner motd # Enter TEXT message. End with the character '#'. It's Gyan Prakash & Sadhana Company. If you are not an authorized person immediatly Logout from the network. Thanks, Have a Nice Day. # Mumbai(config)#^Z %SYS-5-CONFIG_I: Configured from console by console Mumbai#copy running-config startup-config Destination filename [startup-config]? Building configuration... [OK] Mumbai# To view the IP routing table created on a Cisco router, use the command show ip route. The command output is shown as follows: Mumbai#sh ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area

9 IP Routing Configuration in a Router with Troubleshooting * - candidate default, U - per-user static route, o - ODR P - periodic downloaded static route Gateway of last resort is not set /24 is subnetted, 2 subnets C is directly connected, FastEthernet0/0 C is directly connected, FastEthernet0/1 Mumbai# The Mumbai serial interface 0/2/0 and Serial 0/2/0 both are a DCE connection, which need to add the clock rate command to the interface. Mumbai(config)#int serial0/2/0 Mumbai(config-if)#clock rate? Speed (bits per second < > Choose clockrate from list above Mumbai(config-if)#clock rate Mumbai(config-if)# %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/2/0, changed state to up Mumbai(config-if)#bandwidth? < > Bandwidth in kilobits Mumbai(config-if)#bandwidth 64 Mumbai(config)#int serial0/2/1 Mumbai(config-if)#clock rate Mumbai(config-if)#bandwidth 64 Mumbai(config-if)#^Z %SYS-5-CONFIG_I: Configured from console by console

10 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al. 102 Mumbai#sh controllers serial 0/2/0 Interface Serial0/2/0 Hardware is PowerQUICC MPC860 DCE V.35, clock rate Mumbai#sh controllers serial 0/2/1 Interface Serial0/2/1 Hardware is PowerQUICC MPC860 DCE V.35, clock rate V. CHENNAI ROUTER CONFIGURATION First we erase the startup-configuration and reload the router. Router>en Router#erase startup-config Erasing the nvram filesystem will remove all configuration files! Continue? [confirm] [OK] Erase of nvram: complete %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram Router#reload Proceed with reload? [confirm][enter] [Outputs cut] --- System Configuration Dialog --- Continue with configuration dialog? [yes/no]: no Press RETURN to get started! Router>en Router# Now we can start to configure the router. Router#config terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)#hostname Chennai Chennai(config)#enable secret Sana Chennai(config)#interface serial0/0/0 Chennai(config-if)#ip address Chennai(config-if)#description WAN Connection to Mumbai Router. Chennai(config-if)#no shutdown %LINK-5-CHANGED: Interface Serial0/0/0, changed state to up Chennai(config-if)# %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0, changed state to up Chennai(config-if)#interface fastethernet 0/1 Chennai(config-if)#ip address

11 IP Routing Configuration in a Router with Troubleshooting Chennai(config-if)#description LAN Connection to PC4. Chennai(config-if)#no shutdown %LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up Chennai(config-if)#interface fastethernet 0/0 Chennai(config-if)#ip address Chennai(config-if)#description LAN Connection to PC5. Chennai(config-if)#no shutdown %LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up Chennai(config-if)#line console 0 Chennai(config-line)#password Sana Chennai(config-line)#login Chennai(config-line)#line vty 0? % Unrecognized command Chennai(config-line)#exit Chennai(config)#line vty 0? <1-15> Last Line number <cr> Chennai(config)#line vty 0 15 Chennai(config-line)#password Sana Chennai(config-line)#login Chennai(config-line)#exit Chennai(config)#banner motd # Enter TEXT message. End with the character '#'. It's network of Gyan Prakash & Sadhana Company. If you are not an authorized person immediatly Logout from the network. Thanks, Have a Nice Day. # Chennai(config)# Chennai(config)#^Z %SYS-5-CONFIG_I: Configured from console by console Chennai#copy running-config startup-config Destination filename [startup-config]? Building configuration... [OK] Chennai# To view the IP routing table created on a Cisco router, use the command show ip route. The command output is shown as follows: Chennai#sh ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

12 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al. 104 N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic downloaded static route Gateway of last resort is not set /24 is subnetted, 3 subnets C is directly connected, Serial0/0/0 C is directly connected, FastEthernet0/1 C is directly connected, FastEthernet0/0 Chennai# Chennai#config t Enter configuration commands, one per line. End with CNTL/Z. Chennai(config)#interface serial 0/0/0 Chennai(config-if)#bandwidth 64 Chennai(config-if)#^Z %SYS-5-CONFIG_I: Configured from console by console Chennai#sh controllers serial 0/0/0 Interface Serial0/0/0 Hardware is PowerQUICC MPC860 DTE V.35 TX and RX clocks detected Let s take a look at our configuration of the interfaces. User Access Verification Password: Delhi>en Password: Delhi#sh protocols Global values: Internet Protocol routing is enabled FastEthernet0/0 is up, line protocol is up Internet address is /24 FastEthernet0/1 is up, line protocol is up Internet address is /24 Serial0/0/0 is administratively down, line protocol is down Serial0/0/1 is administratively down, line protocol is down Serial0/2/0 is up, line protocol is up Internet address is /24 FastEthernet1/0 is administratively down, line protocol is down FastEthernet1/1 is administratively down, line protocol is down Vlan1 is administratively down, line protocol is down Delhi# User Access Verification

13 IP Routing Configuration in a Router with Troubleshooting Password: Mumbai>en Password: Mumbai#sh protocols Global values: Internet Protocol routing is enabled FastEthernet0/0 is up, line protocol is up Internet address is /24 FastEthernet0/1 is up, line protocol is up Internet address is /24 Serial0/0/0 is administratively down, line protocol is down Serial0/0/1 is administratively down, line protocol is down Serial0/2/0 is up, line protocol is up Internet address is /24 Serial0/2/1 is up, line protocol is up Internet address is /24 FastEthernet1/0 is administratively down, line protocol is down FastEthernet1/1 is administratively down, line protocol is down Vlan1 is administratively down, line protocol is down Mumbai# Chennai#sh protocols Global values: Internet Protocol routing is enabled FastEthernet0/0 is up, line protocol is up Internet address is /24 FastEthernet0/1 is up, line protocol is up Internet address is /24 Serial0/0/0 is up, line protocol is up Internet address is /24 Serial0/0/1 is administratively down, line protocol is down Serial0/1/0 is administratively down, line protocol is down FastEthernet1/0 is administratively down, line protocol is down FastEthernet1/1 is administratively down, line protocol is down Vlan1 is administratively down, line protocol is down Chennai# Now we can check the brief summary of router interfaces.

14 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al. 106 Mumbai# sh ip inter bri Interface IP-Address OK? Method Status Protocol FastEthernet0/ YES manual up FastEthernet0/ YES manual up up up Serial0/0/0 unassigned YES manual administratively down down Serial0/0/1 unassigned YES manual administratively down down Serial0/2/ YES manual up up Serial0/2/ YES manual up up FastEthernet1/0 unassigned YES manual administratively down down FastEthernet1/1 unassigned YES manual administratively down down Vlan1 unassigned YES manual administratively down down Mumbai# The show ip route command displays the following: Mumbai#sh ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic downloaded static route Gateway of last resort is not set /24 is subnetted, 4 subnets C is directly connected, Serial0/2/0 C is directly connected, Serial0/2/1 C is directly connected, FastEthernet0/0 C is directly connected, FastEthernet0/1 Mumbai#

15 IP Routing Configuration in a Router with Troubleshooting We have checked the proper router configuration with the help of show protocols, show ip interface brief and sh ip route commands.so now we will check the IP network connectivity between two routers through ping response by sending IP packets.ping to the Mumbai router from Delhi router. Delhi#ping Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to , timeout is 2 seconds:!!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 36/45/56 ms In the above example Delhi router sent 5 IP packets and Mumbai router received all 5 packets, so network connectivity between both routers is ok. VI. CONCLUSION To make a live network, it is must to configure the router hostname, passwords, message of the day (motd), interfaces, IP addresses, descriptions, clock rate, bandwidth etc. But no shutdown command is must to bring up an interface otherwise interface will show administratively down. After complete configuration you should check the network connectivity between two routers by ping response. In this paper a small network has shown and if you configure this network, then you are able to configure a big network, using more routers and same configuration commands. VII- REFERENCES [1] S. Keshav and R. Sharma, Issues and Trends in Router Design, IEEE Communications Magazine, vol. 36 no. 5, pp , May [2] Perlman, R. Interconnection: Bridges, Routers, Switches and Internetworking Protocols. Reading, MA: Addison-Wesley, [3] S. Halabi and D. McPherson, Internet Routing Architectures. Cisco Press, second ed., [4] Yuan R. and Strayer, W. Virtual Private Network. Reading, MA: Addison-Wesley, [5] L. Kleinrock and F. Kamoun. Hierarchical routing for large networks: Performance evaluation and optimization. Computer Networks, Vol. 1, pp [6] M. Grossglauser and J. Rexford,.Passive traffic measurement for IP operations,in The Internet as a Large-Scale Complex System, Oxford University Press. [7] S. Halabi and D. McPherson, Internet Routing Architectures. Cisco Press, second ed., [8] A. Feldmann, A. Greenberg, C. Lund, N. Reingold, and J. Rexford,.NetScope: Traffic engineering for IP networks. IEEE Network Magazine, pp , March [9] B. Fortz and M. Thorup,.Internet traffic engineering by optimizing OSPF weights,. in Proc. IEEE INFOCOM, March [10] B. Fortz and M. Thorup,.Optimizing OSPF/IS-IS weights in a changing Selected Areas in Communications, vol. 20, pp , May [11] D. O. Awduche,.MPLS and traffic engineering in IP networks,. IEEE Communication Magazine, pp , December [12] P. Newman, T. Lyon, and G. Minshall, Flow Labelled IP: A Connectionless Approach to ATM, Proc IEEE Infocom 96, San Francisco, CA, March 1996, pp [13] A. Bianco, R. Birke, Control and management plane in a multi-stage software router architecture, High Performance Switching and Routing, pp , May [14] C. Huitema, Routing in the Internet, Prentice Hall, [15] V. Fuller et al. Classless Inter-Domain Routing, IETF RFC 1519, Jun [16] D.C. Feldmeier, Improving Gateway Performance with a Routing-Table Cache, Proc. IEEE Infocom 88, New Orleans, LI, Mar

16 IJECSE,Volume1,Number 1 Gyan Prakash Pal et al. 108 [17] M. Zitterbart et al., HeaRT: High Performance Routing Table Lookup, 4th IEEE Workshop on Architecture & Implementation of High Performance Communications Subsystems, Thessaloniki, Greece, Jun [18] P. Gupta, S. Lin, and N. McKeown, Routing Lookups in Hardware at Memory Access Speeds, Proc. IEEE Infocom 98, Mar [19] E. Perkins and K. Y. Wang, Optimized Smooth Handoffs in Mobile IP. Proceedings of the IEEE Symposium on Computers and Communications, Red Sea, Egypt, June [20] D. Stiliadis and A. Verma, Providing Bandwidth Guarantees in an Input-Buffered Crossbar Switch, Proc. IEEE Infocom 95, 1995, pp [21] P. Marimuthu, I. Viniotis, and T. L. Sheu, A Parallel Router Architecture for High Speed LAN Internetworking, 17th IEEE Conf. on Local Computer Networks, Minneapolis, Minnesota, Sept