Network Concepts Communications Networks Need for Communications Networks Voice Communications Data Communications Transmitting Images Fax Video Analog and Digital Signals Types of Cabling Data Communications Information from PC to LAN to WAN Protocols: What, Why? Transmission Modes Data Connectivity Data Character and Frame Formats Transmission Methods Error Detection Data Compression Techniques Physical Links and Interfaces Protocols Fundamentals OSI/RM Physical link Link layer Network layer Routing services Transport layer Session layer Presentation layer Application layer Stack References DOD stack Novell stack IBMs SNA Link Level Transmission Procedures Link layer service connectionless vs. connection-oriented Service comparisons Service access point (SAP) subnetwork access protocol (SNAP) Encapsulation methods LAN access methods CSMA/CD IEEE 802.5 Token Ring ethernet verion II Novell frame formats addressing Source routing Transparent spanning tree Logical link control (LLC) WAN link services Other lilnk level protocols HDLC LAPB SLIP X.25 SDLC PPP frame relay SMDS and ATM cells Network Layer Protocols Network layer services Network layer vs. OSI/RM Routing services Security and performance consideration TCP/IP services TCP IP UDP ICMP DOD/IP addressing Subnetworked addressing Routing information protocol (RIP) RIP loop prevention open shortest path first (OSPF) ARP and RARP Other network layer protocols ES-IS CLNP NSAP Novell NetWare IPX IPX address structure SPX packet structure AFP AppleTalk vs. the OSI/RM Datagram delivery protocol (DDP) Packet formats Address selection and resolution WAN routing protocols OSPF RIP EGP Transport Layer Connection-oriented services Transport error checking Transmission control TCP protocol characteristics OSI transport service Novell transport services Novell NCP burst mode Upper Layer Services Session layer connection IBM SNA vs. OSI/RM OSI network management Simple network management protocol (SNMP) CMIP CMOT MIBS High Performance LAN Protocols LAN performance shared vs. dedicated bandwidth Ethernet switching technology Token Ring switching ATM migration IBM SNA Networking SNA VTAM vs. APPC SNA vs. OSI Spoofing 3270 LAN integration NetBIOS Logical units (LU) and physical units (PU) Basic link unit (SDLC) SNA/LAN integration Cisco SDLLC--IBM DLS TCP/IP and the Internet Cabling LAN Media Access Control (MAC) WAN Access Control Media Access Equipment: NICs, DCEs LANs LAN applications and uses Peer-to-peer LANs Client-server LANs Types and uses of servers print fax mail file web ftp other gopher archie whois X.500 finger authentication (kerberos, etc.) Ethernet (IEEE 802.3) Overview Operation and frame structure Ethernet options 10Base-T 10Base-2 10Base-5 10Base-FL FOIRL Ethernet components: repeaters tranceivers Traffic characteristics Strengths and weaknesses Token Ring (IEEE 802.5) Overview Operation and frame structure Token Ring options: 4Mbps 16Mbps Cabling considerations Token Ring electronics Traffic characteristics Strengths and weaknesses Logical Link Control LAN Technologies FDDI Overview Operation and frame structure Multimode Single-mode TP-PMD: Category 5 UTP FDDI electronics Traffic characteristics Strengths and weaknesses 100 Mbps Ethernet LAN switching Specialty LAN products IP switching MAC switching WANs WAN applications and uses WAN infrastructure Public and Private networks Switched and Leased digital lines WAN service access lines Voice networks Telephone companies Common carriers Private carriers Basic WAN services Switched 56Kbps ISDN FT-1, FT-3: applications, encoding, and fractional T-1 SONET OC-1 ATM Frame Relay X.25 SMDS DCE Equipment Modems CSUs/DSUs Multiplexing Inverse multiplexing Network Circuit Connectivity MANs MAN Services FDDI MANs Distributed Queue Dual Bus SMDS MAN Service Providers MAN Applications Internetworking Internetworking Devices Repeaters Bridges Bridge architecture Bridge operation learning process filtering database spanning tree configuration sizing and buffering Types of bridges and how they work tranparent spanning tree source routing tranlational and encapsulating Bridging applications Routers Functional definition Protocol dependent vs. media independent Types of routers Routing techniques routing and distance vector algorithm link state algorithm Routing applications Router installation protocol naming conventions sharing addresses subnet definitions Router configuration Interior routing protocols IP/RIP IGRP OSPF IPX/RIP IPX/NLSP BGP Exterior routing protocols Switches Functional definition cut-through vs. store and forward hybrid designs Types of switches Switching applications virtual LAN support segmentation mixed-media LAN switching switch integration backbone strategies Gateways LAN and WAN Equipment Routing Protocols Routing information protocol (RIP) Open shortest path first (OSPF) Intergateway routing protocol (IGRP) Internet protocol (IP) Routing with TCP/IP Routing with Novell Netware IPX Novell addressing SAP network services NetWare core protocol (NCP) Novell NetWare IPX routing (RIP & NLSP) Router configuration Routing tables Network management Fault management Performance management Security and account management SNMP agents and MIBs Backbone internetworking strategies Centralized vs. distributed Backbone migration options parallel ethernets / Token Rings star-wired Token Rings high-speed backbones Collapsed backbone strategies AppleTalk protocol and routing AppleTalk addressing AppleTalk phases I and II Bridging vs. routing Cost, purpose, expertise Transmission reliability Transmit and response time Physical growth Performance enhancements Troubleshooting bridges and routers Verify bridge filtering operation address filters protocol filters Verify router configuration operation duplicate address problems bridge and router performance problems examine bridge and router table updates minimalizing broadcast storms Performance considerations LAN to LAN, LAN to WAN Traffic patterns and frame distributions throughput bursty traffic large packets Optimal performance strategies segmentation design tunneling encapsulation translation Switching Overview Ethernet Token Ring FDDI ATM Interconnecting LANs Interconnecting WANs Network Software and Operating Systems Computer Operating Systems MS-DOS Windows 95, NT MacOS Unix Network Operating Systems (NOSs) Novell Netware Windows NT (, 95) Unix OS/2 AppleTalk TCP/IP Overview Stacked Protocols and Standards XNS, SNA, OSI TCP/IP history Standards control RFCs, FYIs TCP/IP Stack Overview Layer responsibilities process layer FTP, TELNET, SMTP, DNS, RIP host-to-host layer TCP UDP internet layer IP, ARP, ICMP, EGP, OSPF network interface layer ethernet, Token Ring, SLIP, PPP Standard RFCs by layer Network Interface Layer Ethernet II headers packet information IEEE 802.3, 802.5, SLIP, PPP IP Networks, Subnets, and Hosts IP addressing IP communications logic process Subnetting IP networks applying the mask when to subnet Address Matching Hosts file DNS Address resolution protocol (ARP) Reverse address resolution protocol (RARP) Boot protocol (BOOTP) Internet Protocol The self-healing network IP header layout 32-bit ruler header precedence bits type of service (TOS) total IP length datagram ID number fragmentation time to live (TTL) shipping label from and to versions checksum IP options Sample IP header decodes User Datagram Protocol (UDP) Speed vs. reliability Header breakdown Application requirements IP Routing Routing vs. bridging Routers and gateways naming and IP addressing issues Direct vs. indirect routing Manual vs. automatic routing Exterior protocols autonomous systems exterior gateway protocol (EGP) Interior protocols routing information protocol (RIP) open shortest path first (OSPF) compatibility benefits vs. RIP multiple routes load balancing link state balancing variable subnet implementation masking address management border gateway protocol (BGP) Internet Control Message Protocol (ICMP) Messages variations diagnostic error reporting where they go Basic format types codes checksum Diagnostic protocol support ping type 8: echo request type 0: echo reply type 13: time stamp request type 14: time stamp reply type 17: mask request type 18: mask reply Variation/error reporting type 3: destination unreachable type 4: source quench type 5: redirect type 11: time exceeded type 12: parameter problems Reliable Sessions and TCP Connection-oriented process Header fields Session termination methods Telnet What telnet can do, when to use it Network virtual terminal TN3270 TCP/IP Network Security Issues Reality check Encryption Internal External File Transfer Protocol (FTP) What FTP is used for Commands Response codes Command/response sequnces in a live session Simple Mail Transfer Protocol (SMTP) Commands Response codes Multipurpose Internet Mail Extensions (MIME) SMTP futures Automated TCP/IP Configuration Reverse address resolution protocol (RARP) Boot protocol Dynamic host configuration protocol (DHCP) compared to BOOTP virtual IP networking Trivial File Transfer Protocol (TFTP) Variation on client/server implementation Functions Sorcerer's apprentice Simple Network Management Protocol (SNMP) An SNMP model management station agent MIBs Version one commands Version two commands SNMP and DMI and SMS TCP/IP Internet Services Uniform resource locators (URL) Archie servers commands parameters Gopher menu interconnections veronica jughead World wide web home page Netscape Lynx TIA HotJava Access methods PPP vs. SLIP dial-up direct Strengths and Weaknesses IPng (IPv6) 3 major contenders TUBA CATNIP SIPP IPv6 working group New header Migration plans Extensions TCP/IP and NOSs Network Planning and Management Network Management Tools Network Management Strategies Design and documentation Proactive vs. reactive management Escalation procedures Network workaroung logs Network statistics Simple Network Mangement Protocol (SNMP) Understanding SNMP concepts an SNMP model: NMSs, OIDs, and Agents protocol data units request and response flow SNMP communications concepts in-band over ethernet_II, IPX, TCP/IP out-of-band IP protocol structure Protocol data units structure of management information SMI and MIBs MIB object definitions ASN.1 tag classes, formats, and types SNMPv2 changes MIBs MIB tree groups inbound and outbound counters MIB extensions Which MIBs do I poll? RMON RMON probes on-line vs. on-demand operations network statistics performance monitoring problem detection and reporting RMON MIB extensions RMON groups Agents smart agents proxy agents extensible agents super agents Network Management Platforms Protocol Analyzer Fault Management Performance Management Statistical Analysis Network Monitoring Application metering Baselines and trend analysis Broadcasts Response time Retransmissions Bandwidth and throughput Routing Traffic characterization Optimization Troubleshooting Cable testers Protocol analyzers analyzer types monitor vs. capture analyzer strategies reading the displays filtering techniques Methodology gather information isolate the problem apply corrective measures monitor results Layer functions network interface layer internetwork layer host-to-host (transport) layer application layer RFC 1147 ICMP Documentation Informed users Configuration Management Network Planning Overview Capacity analysis Needs analysis Budget issues Staffing needs Security issues Documentation Help desk Backups Training Long-term planning strategies Network Security Administration Overview Defining the problem What are you trying to protect? What makes a good security policy? Issues of security policy design Who are you trying to protect it from? motivation for computer break-ins types and methods of attacks More reasons for network insecurity How much are you willing to spend? Categories of computer security Incident response Legal considerations Emerging Technologies Benefits and Applications ADSL, HDSL, SDSL H0, H11, H12 Channels Virtual LANs Fast Ethernet 100Base-T4 100Base-TX 100Base-FL 100VGAny LAN ATM Iso - Ethernet 1Gbps Ethernet Fiber Channel Wireless Networks LABS 1: Build a classroom network--we will use 20 MacPlus's and an IBM PS/2 Model 30, in conjunction with a Tribestar Ethernet- LocalTalk bridge 2: Verify PC and Mac hardware and configuration--learn how to determine the component parts of the hardware and how to make the software make use of them 3: View network traffic--use a protocol analyzer to capture and analyze traffic on your network--TCP/IP, Appletalk, IPX/SPX 4: Analyze network packet frame structure--using the protocol analyzer, examine the structure of network packets 5: Configure TCP/IP networking on the lab machines--utilize a Class C network, employ proper subnetting, and correct static and default routing--troubleshoot using ping, traceroute 6: Create a file server--using AFP, FTP, SAMBA 7: Load a Novell Netware protocol stack--we will connect to the Blair Media Center Novell file server 8: Route network traffic--create router services on one of the lab computers--turn a computer host into a router 9: Observe demo of a tranparent bridge and the limitations of a remote bridge 10: Observe and analyze live router-to-router communications 11: Observe and analyze IP networking protocols on the lab network--precedence, type of service, fragmentation, and protocol used 12: Observe and analyze Novell client/server session 13: Observe an IP tunneling demonstration of IPX encapsulated within IP 14: Observe a demo of Novell's burst mode operation over a WAN 15: Analyze a session using File Transfer Protocol (FTP) between a server and a client 16: Analyze an ARP cache to determine which IP addressed systems your computer has called 17: Analyze fields in ARP header to identify requests and replies captured live on the lab network 18: Locate and analyze a message that runs over UDP--establish destination application, length of header, and application data in the packet 19: Analyze RIP messages--determine the protocol of the advertised networks; examine RIP message layout and compare to an IP routing table 20: The instructor generates in ICMP diagnostic message--students locate the echo response and its matching reply on the network 21: Analyze and decode ICMP error report message 22: Analyze and decode TCP header--determine the current position in the network; demonstrate how TCP can establish connectivity and virtual circuitry across a network 23: Track a live telnet session in the lab network from the negotiations through login, password, and exit 24: Configure your computer's email client and track a test message to the lab SMTP server; learn to read the decoded SMTP packets in the command response through a live lab email session 25: Track a live HTTP session from a lab computer to the lab HTTP server 26: Configure your TCP/IP computer to use DHCP to automatically configure the other computers in the lab 27: Capture/analyze network traffic 28: Ethernet switch and tranparent bridge functions 29: Configure MAC-layer bridges and spanning-tree 30: Analyze transparent bridge spanning-tree 31: Configure IP/RIP network 32: Configure IPX/RIP network 33: Configure AppleTalk/RTMP network 34: Establish a baseline for the performance of the lab network; identify specific steps to take when baselining network performance 35: Use ping and traceroute to identify and isolate connectivity problems 36: Use nslookup and dig to diagnose DNS problems 37: Use netstat to identify problems with routing 38: Retrieve an SNMP Get Request message from the lab network and identify the ASN.1 details 39: Capture a SNMP trap response message from the lab network and identify its components and functions 40: Compile a Private MIB Extension on the workstation for use in retrieving data from the lab network agents 41: Retrieve SNMP MIB I, MIB II, and private MIB data from several different lab agents 42: Compile RMON MIB extensions on the workstation and utilize them to access classroom network information 43: Retrieve data from a classroom networked RMON probe located on a remote segment 44: Develop a security policy for the lab network and your site 45: Use stubs and TCP Wrappers to secure network services on your host 46: Use SATAN, ISS, Tripwire, and a variety of other logging and auditing tools to identify and close potential security holes on your network 47: Configure Cisco screening routers to protect your subnetwork from the rest of the lab network; identify different packet filtering policies and examine how configuring the router affects access and performance 48: Configure and test secure messaging using PGP 49: Configure TIS Firewall Kit; setup and configure access rights and proxy services