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Data Networking. Craig E. Canevit Network Services University of Tennessee April 12, 2005. What is Data Networking?. A computer network is “an interconnection of computers and computing equipment using either wires or radio waves over small or large geographic areas.”. Types of Networks:.
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Data Networking Craig E. Canevit Network Services University of Tennessee April 12, 2005
What is Data Networking? A computer network is “an interconnection of computers and computing equipment using either wires or radio waves over small or large geographic areas.”
Types of Networks: • P2P (Peer to Peer) • Client/server • WAN (Wide Area Network)
WAN vs. MAN vs. LAN vs. PAN vs. WLAN… • MAN (Metropolitan Area Network) • LAN (Local Area Network) • PAN (Personal Area Network) • WLAN (Wireless LAN) • Geographical vs. topological vs. technological distinctions
Unbelievably Brief History of Data Networking In the 1960s, DARPA (Defense Advanced Research Projects Agency, US Military’s R&D) started looking into connecting computers through networks, particularly packet-switched networks. Its work led to the formation of ARPANET in the late 1960s, which gradually evolved into the Internet. • DNS • Subnetting
The OSI Model & Why It Matters • ISO (International Organization for Standardization) • ISO vs. Open Systems Interconnection • Application • Http, ftp, telnet, ssh • Presentation • ASCII/encryption/compression • Session
The OSI Model, continued • Transport • End to end • Network (packets) • L3 addressing (i.e.: 160.36.193.46 ) • Next hop • Data Link (frames) • L2 addressing (i.e.: 0002.fea8.39c1) • SSN vs. postal service • Physical
Encapsulation • Application Application • Presentation Presentation • Session Session • Transport Transport • Network Network • Data Link Data Link • Physical Physical
Network Protocols • AppleTalk • SPX/IPX (Sequenced Packet EXchange/Internet Packet EXchange) • NETBEUI/NetBIOS (NetBIOS Extended Interface) • TCP/IP protocol suite
Binary, Bits & Bytes • Bits: 0 vs 1 • Decimal: Powers of 10 • 2,165 = • 2*103+1*102*6*101+5*100 • Binary: Powers of 2 • 2165= • 100001110101 or • 211+26+25+24+22+20 or • 2048+64+32+16+4+1
Binary, Bits & Bytes (traditionally) • Byte = 8 bits • Kilobyte (KB) = 1024 bytes (or 8192 bits) • Megabyte (MB) = 1024 kilobytes • Gigabyte (GB) = 1024 megabytes • Terabyte (TB) = 1024 gigabytes
Maybe Bites? (IEC Standard) • Byte = 8 bits • Kilobyte (kB) = 1000 bytes vs. Kibibyte (KiB) = 1024 bytes • Megabit (Mbit) 1000 Kilobits vs. Mebibyte (MiB) = 1024 kibibytes vs. Megabyte (MB) = 1000 megabits • International Electrotechnical Commission
WAN Technologies • T-/DS-/OC- lines • Based on telephone lines DS-0 = 64 kbps) • T1 = 1.544 Mbps (or 24 DS-0 lines) • DS-3 = 44.736 Mbps • OC-12= 622.08 Mbps • Cell switching: • SONET (Synchronous Optical NETwork) • ATM • ISDN (Integrated Services Digital Network) • 128Kbps/1.54Mbps • Frame Relay (typically low speeds: 56K-T1 speeds)
MAN Technologies • In-between LAN & MAN
LAN Technologies • Cable Modems (1.5 - 6 Mbps down, 256 - 768 kbps up) • Wireless ( 802.11b = 11 Mbps, 802.11a or 6 = 54 Mbps) • Ethernet (10/100/1000/10Gbps) • 10Base-2 • 10/100/1000Base-T • Modems (56kbps) • DSL (1.544 Mbps to 512 Kbps downstream and about 128 Kbps) • LRE (5/10/15 Mbps)
Network Cabling • UTP, STP • Cat 5 (allows for up to 150 Mbps) • Cat 6 (allows for 1 Gbps) • Coax • 10 Mbps for Ethernet (500 Mbps) • Fiber
Network Topologies • Ring • Token-based • Bus/tree • Contention • Star • Contention • Ethernet: CSMA/CD
Network Devices • So far: protocols, topologies, types of networks • Bridges/Hubs/Repeaters • Switches • ASICs versus software • Routers
Network Devices • Bridges
Network Devices • Switches
Network Devices • Routers
Security Concerns • Firewalls • ACLs • Routers with “firewall feature set” • VPNs • IDS/IPS & network sniffing • 10-Base2 LANs • Cable modem networks • Hubs • Wireless
Vendors • Cisco • Linksys • Extreme • Nortel • HP • Enterasys • Juniper • Foundry
What Do We Have at UTK? • About 780 Cisco switches • Most buildings have Gigabit Ethernet uplink • 8 main Cisco routers • Several dozen DEMPRs • 1100 Access Points supporting 802.11g • Juniper router at the border • 622 Mbps (135 for I1, 487 for I2) • Resnet DS-3 (45 Mbps) • ISDN connections, • DSL services
What Do We Have at UTK? (continued) • FDDI (Fiber Distributed Data Interface) to Pellissippi • Modem Pool (~250 users) • LRE, DSL to buildings • T-1s to Middlebrook, etc. • Direct 100 Mbps connection to Lexis-Nexis
Special Applications • Packeteer Packetshaper • Tipping Point IPS • VLANs • DNS
Standards/Governing bodies • EIA/TIA (Electronic Industries Alliance/Telecommunications Industry Alliance) • IETF (RFCs) • IEEE (Institute of Electrical and Electronics Engineers) • InterNIC • ARIN • IP address space
Speaking of Address Space • IPv6 (128 bit addressing versus IPv4’s 32 bits) • 281,474,976,710,656 addresses versus 2^32 or4,294,967,296 addresses • fe80:0000:0000:0000:0203:93ff:ef76:5a5e vs. 160.36.193.46
The Future? • Move towards IPv6 • VOIP • Convergence • Ubiquitous wireless • Video on demand • 10 Gig E over copper • 100 Gig E