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Computer Networks. Marwan Al- Namari Week 7. Addressing. Network Addressing. A network address consists of two parts: ( i ) Address of the LAN and (ii) Device or host address on that LAN compare with a house address – street name and house number. IP addresses.
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Computer Networks Marwan Al-Namari Week 7
Network Addressing A network address consists of two parts: (i) Address of the LAN and (ii) Device or host address on that LAN compare with a house address – street name and house number
IP addresses Currently there are two types of Internet Protocol (IP) addresses in active use: IP version 4 (IPv4) and IP version 6 (IPv6). IPv4 was initially deployed on 1 January 1983 and is still the most commonly used version. IPv4 addresses are 32-bit numbers often expressed as 4 octets in "dotted decimal" notation Deployment of the IPv6 protocol began in 1999. IPv6 addresses are 128-bit numbers and are conventionally expressed using hexadecimal strings
IP addresses authorities If you are connecting to the Internet, you will need to get a registered IP address from the agency that governs IP addresses, this was the InternetAssigned Numbers Authority (IANA) now done by ICANN... or from an Internet Service Provider (ISP) that has already obtained blocks of addresses from an Internet Registry
Dotted Decimal notation TCP/IP addresses are represented by the so-called 'dotted decimal' notation. This allocates decimal numbers to the 32 bits in 4 fields each representing 8 bits. e.g. 10000000 00001010 00000010 00011110 becomes 128 . 10 . 2 . 30
IP v.6 The next generation of the Internet protocol, IP v.6, the deployment of which began in 1999, It has an almost unlimited range of addresses, so sub netting to conserve IP addresses should no longer be a problem. IPv6 addresses are 128-bit numbers and are conventionally expressed using hexadecimal strings (for example, 1080:0:0:0:8:800:200C:417A). If the router does not support IPv6 we use TUNNELING .
Tunneling (1) Connects two networks through a middle one Packets are encapsulates over the middle
Tunneling (2) Tunneling analogy: tunnel is a link; packet can only enter/exit at ends
Available addresses N.B K=1024 , M=1024K 127.0.0.0 = special diagnostic address- e.g. loopback =127.0..0.1
Example: Class B IP Addressing Network number is 145.10.0.0 First station address is 145.10.0.1 Second station address is 145.10.0.2 etc. Last station address is ? Broadcast address is 145.10.255.255
Default subnet masks 255.0.0.0 for class A 255.255.0.0 for class B 255.255.255.0 for class C
Example 2 Class C address The IP address 201.107.2.200 = 11001001 01101011 00000010 11001000 The default class C mask is 255.255.255.0 = 11111111 11111111 11111111 00000000 When the mask is ANDed with the IP address it leaves the network part of the address: 11001001 01101011 00000010 11001000 11111111 11111111 11111111 00000000 __________________________________ 11001001 01101011 00000010 00000000 = The last eight places are all zeros, which translates to 0. and 200 would be the host_id on the network 201.107.2.0. N.B. Zero in the last place means we don’t care what the host number is; all we are looking at is the network number.
Private IP addresses 10.0.0.0 to 10.255.255.255 172.16.0.0 to 172.31.255.255 192.168.0.0 to 192.168.255.255 APIPA : Automatic Private IP Address range 169.254.0.0 to 169.254.255.255
APIPA Automatic Private IP Address Range 169.254.0.0 thru 169.254.255.255 Used on small LANs without DHCP server (on a single-subnet network that contains no routers). Assigns only an IP address and subnet mask Broadcasts are used to ensure there are no address conflicts Available on Windows 98 and 2000/XP PCs
DHCP DHCP: DYNAMIC HOST CONFIGURATION PROTOCOL Client server service Client configured for DHCP will seek out a DHCP Server, using broadcasts, in order to obtain a IP address automatically.
