10/27/2015 1R. Smith - University of St Thomas - Minnesota CISC Class Today Structured WiringStructured Wiring A wiring closetA wiring closet Ethernet continuedEthernet continued Wiring exerciseWiring exercise ARPARP DHCPDHCP LabLab

10/27/2015 2R. Smith - University of St Thomas - Minnesota Structured Wiring Standard layout for multifloor buildingsStandard layout for multifloor buildings –Horizontal cable, backbone (vertical cable), external cable LayoutLayout –Wiring plugs attached to horizontal wiring –Horizontal wires collect in wiring closets on each floor –Vertical wire serves as ‘backbone’ to connect floors –Backbone connects on ground floor to external cable

10/27/2015 3R. Smith - University of St Thomas - Minnesota Tour Time Back soon.Back soon.

10/27/2015 4R. Smith - University of St Thomas - Minnesota Routing Exercise Net ArchitectureNet Architecture –Hosts A and B are on LAN 1 –Hosts C and D are on LAN 2 –Hosts E and F are on LAN 3 –B and C are connected via L3 router –D and E are connected via firewall with NAT (E, F “inside”) Do these get through?Do these get through? –Host A with MAC address for B; with MAC addr for C –Host A with Internet address for C; with Internet address for F –Host F with Internet address for A –Host F with MAC address for A; MAC address for C Add routingAdd routing

10/27/2015 5R. Smith - University of St Thomas - Minnesota Ethernet Classic and Fast EthernetClassic and Fast Ethernet –10baseT, 100baseT –“Bus” topology –CSMA/CD access to the bus Gigabit EthernetGigabit Ethernet –1000baseT, 10Gbase-S, -L, -E (short, long, extended) –Interconnected stars –Switched access

10/27/2015 6R. Smith - University of St Thomas - Minnesota Addressing on a LAN Address Resolution ProtocolAddress Resolution Protocol Mapping MAC to IP and backMapping MAC to IP and back –Requester wants to know a target’s MAC address (knows IP) –Requester sends a ‘broadcast’ –Someone (usually the ‘target’) answers “Reverse ARP”“Reverse ARP” –Given a MAC address, get the IP address –An early form of boot-up configuration Looking at ARP via WiresharkLooking at ARP via Wireshark

10/27/2015 7R. Smith - University of St Thomas - Minnesota DHCP Dynamic Host Configuration ProtocolDynamic Host Configuration Protocol –Also sometimes called ‘bootp’ (i.e. in Wireshark) Used when a host boots upUsed when a host boots up –The host sends a broadcast query Uses UDP (ports 67 & 68); client usually ID’d with its MAC addrUses UDP (ports 67 & 68); client usually ID’d with its MAC addr Routable – relies on ‘forwarding agents’ in routersRoutable – relies on ‘forwarding agents’ in routers –A DHCP server responds with initial IP configuration data Typical configuration dataTypical configuration data –Host’s assigned IP address (may be temporary w/expiration) –Address of default gateway (router), and network mask –Address(es) of DNS server(s) to use –Other useful info (Windows server addresses)

The Lab Lab Objective: map the lab machinesLab Objective: map the lab machines Lab GroupsLab Groups –I’ve assigned groups via – I’ll also post groups –Do the labs as a group (this one and future ones) –If you want to trade group members, talk to me FIRST Where to do itWhere to do it –Lab upstairs – OSS 428 When to do itWhen to do it –I’ll set up a schedule 10/27/2015 8R. Smith - University of St Thomas - Minnesota

Let’s visit the lab It’s upstairsIt’s upstairs 10/27/2015 9R. Smith - University of St Thomas - Minnesota

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