2. Training Ethernet and IP Basics

3. Overview OSI Layer Model Ethernet IP ARP IP Routing Higher Layer Protocols VRRP ATM Vision Network Setup Practice

4. Section OSI Layer Model

5. Application Presentation Session Transport Network Data Link Physical Data Transport Physical interface (cable, transceiver etc.) Transmission, framing and error control Data transport Reliability and multiplexing of data transport Adding control mechanism to data transport Structuring of data units Managing of communications OSI: Open Systems Interconnection

6. OSI and Internet Protocol Suite FTP, Telnet, SMTP, SNMP ARP, RARP Presentation IP ICMP Ethernet OSI Reference ModelInternet Protocol Suite NFS XDR PRC Application TCP UDP Session Transport Network Data Link Physical

7. LAN Layer and the OSI Reference Model Data Link Layer MAC Sublayer Physical Layer Ethernet IEEE 802.3 100BaseT Token Ring/IEEE 802.5 FDDI LLC Sublayer IEEE 802.2 OSI LayersLAN Specifiaction

8. Section Ethernet OSI Layer Model

9. Ethernet Frame Preamble Source Address FCS Destination Address TypeData 866246-15004 Field Length, In Bytes FCS = Frame Check Sequence MAC Address: IP Data : 00 : a3 : 25 Vendor specific Vendor ID 00 : 50 : 66 IP Header

10. Section IP (Internet Protocol) OSI Layer Model Ethernet

11. IP Packet VersionIHLType of ServiceTotal Length IdentificationFlagsFragment offset Time to LiveProtocolHeader Checksum Source Address Destination Address Options Data (1 Bytes – 64 kBytes) Padding IHL: Internet Header Length 32 Bit IP Header IP Data

12. IP Addressing IP address comprises 32 Bits, grouped into four octets 32 Bit 8Bit C0A8 192168151 44 97 2C Hex: Dec.:...... 11000000101010001001011100101100 Bin.:...

13. Network Example 192.168.151.44192.168.151.45 192.168.151.215

14. Section ARP (Address Resolution Protocol) OSI Layer Model Ethernet IP

15. ARP ARP: Address resolution protocol Communication between two Ethernet interfaces on a local network based on MAC addresses The address resolution protocol (ARP) provides mapping of an IP address to the unique MAC address

16. ARP MAC address MAC address MAC address MAC address MAC address MAC address MAC address MAC address MAC address MAC address IP: 192.168.151.45 MAC: 00:25:12:34:F2:A3 IP: 192.168.151.16 MAC: 00:25:12:11:BB:C1 IP: 192.168.151.163 MAC: 01:A1:23:8A:45:01 MAC address MAC address

17. Section IP Routing OSI Layer Model Ethernet IP ARP

18. Subnetting With Netmask IP address „ANDED“ with netmask splits net into network and subnet portion 192168151 44 IP Address:... 255 0 Logical AND with Netmask:... Network Subnet 192168151 0...Results in Subnet number: 11000000101010001001011100101100... 11111111 00000000... „AND“ 110000001010100010010111... 00000000

19. Network Example 192.168.172.44 255.255.128.0 192.168.196.63 255.255.128.0 192.168.151.1 255.255.128.0 192.168.13.1 255.255.255.0 Router 192.168.13.234 255.255.255.0 192.168.13.19 255.255.255.0

20. Special IP Addresses Network: 192.168.151.x Netmask: 255.255.255.0 Subnet number: 192.168.151.0 Subnet broadcast: 192.168.151.255 Example: Local host: 127.0.0.1 Multicast groups: 224.0.0.0... 239.255.255.255 Experimental: 240.0.0.0... 254.255.255.255

21. IP Routing Static routing - Static entries in routing table - Setting up Network Interface creates routing entry for local Network - Entries made by administrator - No dynamic changing of entries Dynamic routing - Internet devices investigate their neighbourhood and store the information in the routing table - These information will be collected by special protocols (OSPF, RIP, BGP) Routing maintained by routing table Routing table entries consist of: - Destination IP address - Mask - Gateway - Metric (optional) - Interface (optional) Routing decisions made on “best fit”

22. Section Higher Layer Protocols OSI Layer Model Ethernet IP ARP IP Routing

23. TCP / UDP Connection oriented Connection status available Order guaranteed Assured data transport by the use of: - Flow control - Data verification (checksum) - Data re-transmission in case of lost packets The Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP) work on top of IP. UDP: Connectionless Order guaranteed Duplications removed Unassured data transport (no acknowledge, no re-transmission) TCP:

24. Firewall Devides privat and public Network or two Networks Protects privat Network from unauthorized access Restricts access to or from local machines Firewalling based on rules accept deny reject Rules consists of source and destination IP address and Port (TELNET, FTP, HTTP...) EXTREMLY HARD TO CONFIGURE

25. Firewall HTTP TELNET NETWORK ANETWORK B

26. Masquerading Is located on the same position as the Firewall Only one public IP address needed for whole private Network Often works together with Firewalls on the same machine Exchanges local IP address with the public address 192.168.1.x Public Network Masquerading 192.168.1.x 212.21.117.3

27. Section VRRP OSI Layer Model Ethernet IP ARP IP Routing Higher Layer Protocols

28. VRRP Provides Router Redundancy transparent to hosts All Router must reside on the same Network The machine with the highest priority becomes VRRP mastership Machines with lower priority are VRRP slaves Up to 254 machines for redundancy The master broadcasts VRRP packets If no VRRP packet is received within a defined time, the Slave with the highest priority takes mastership and starts to send VRRP packets and listens on the specified IP address Virtual Router Redundancy Protocol (VRRP)

29. VRRP Simple 1+1 redundancy MasterSlave GW: Master VRRP: Master

30. Section ATM Vision Network Setup OSI Layer Model Ethernet IP ARP IP Routing Higher Layer Protocols VRRP

31. IP Network Settings Enable networking: sysconf net enable Startup Ethernet Interface: sysconf net netmask up : eth0 = Ethernet 1 eth1 = Ethernet 2

32. IP Network Settings Set route to other local networks: sysconf route add –net netmask gw

33. Inband Management Enable Classical IP (CLIP): sysconf clip enable Enable IP forwarding to other interfaces: sysconf net ipforward enable

34. Inband Management Add CLIP destination to routing table: sysconf atmarp add. Configure CLIP interface: sysconf net netmask up Create CLIP interface: sysconf clip interface enable : clip

35. Inband Management CLIP QoS parameter: sysconf clip interface qos =, :,tx:,rx: = ubr | cbr = aal0 | aal5 = valid for tx and rx = pcr=rate | max_pcr=rate | min_pcr=rate | sdu=size | max_sdu=size

36. VRRP root@Karlsruhe:/> sysconf vrrp ? usage: sysconf vrrp sysconf vrrp show sysconf vrrp disable sysconf vrrp priority sysconf vrrp advertise sysconf vrrp preempt enable|disable sysconf vrrp auth none| sysconf vrrp IP { } sysconf vrrp monitor disable| root@Karlsruhe:/> VRRP Parameter: = VRRP ID (identifies the VRRP Network) priority = Router priority on the VRRP ID. Default: 255 = VRRP master advertise = Time interval (in sec.) between two VRRP protocol packets. Timeout after 3 * advertise interval preempt = Allows slave to take over VRRP mastership from slaves with lower priority. VRRP master with priority = 255 always takes mastership auth = Authentication necessary (with password) or not IP = IP-Address(es) to protect monitor = Allows additional monitoring on further connections (ETH0, ETH1 or ATM). Monitoring on ETH0 and ETH1 is only supported on ATM Vision.

37. Checking Connectivity Check IP (Ethernet) connection: ping Tracing route to destination: traceroute Check ATM connection: oam [VCI] -

38. Checking Connectivity The last ressort: tcpdump -i -n [-vv] Establish remote connection: telnet

39. Section Practice OSI Layer Model Ethernet IP ARP IP Routing Higher Layer Protocols VRRP ATM Vision Network Setup

40. Hands On: IP Network Name: IP address: Netmask: Name: IP address: Netmask: Name: IP address: Netmask: Hub Name: IP address: Netmask: Ethernet ATM IP Range: 192.168.x.x

41. Hands on: IP, ATM and VRRP ATM IP Range: 192.168.x.x Ethernet

42. Hands on: IP and CLIP over SVC Name: IP address: Netmask: Name: IP address: Netmask: Name: IP address: Netmask: Name: IP address: Netmask: Ethernet ATM IP Range: 192.168.x.x