Basic Network Management - Chapter 7: TCP/IP

Chapter 7: TCP/IPObjectiveConverting Decimal to binary ( binary to decimal)Decimal to hexadecimal (hexadecimal to decimal)Binary to hexadecimal (hexadecimal to binary)Understanding TCP/IPIP address and SubnettingProtocol for TCP/IPThe Binary SystemComputing devices communicate with 1s and 0sA groups of 8 bits = 1 byteBinary numbers are based on the powers of 2 because there are only 2 symbols: 0 and 1Binary can be converted to decimal in a similar way that decimal numbers are figuredThe Binary System (2)Binary can be converted to decimal in a similar way that decimal numbers are figuredExample: 1010 = (1x23)+(0x22)+(1x21)+(0x20) = (1x8)+(0x4)+(1x2)+(0x1) = 8 + 0 + 2 + 0 1010 = 10The Decimal SystemHumans use the decimal number system base on the powers of 1010 symbols are used: 0,1,2,3,4,5,6,7,8,9In a decimal number, each symbol represents 10 raised to a power according to its position that is then multiplied by that positionThe Decimal System (2)Example: 261 = (2 x 102) + (6 x 101) + (1 x 100) (2 x 100) + (6 x 10) + (1 x 1) 261 = 200 + 60 + 1The Decimal System (3)Converting decimal to binary:Example: 4949/2 = 24 with a remainder of 124/2 = 12 with a remainder of 012/2 = 6 with a remainder of 06/2 = 3 with a remainder of 03/2 = 1 with a remainder of 11/2 = 0 with a remainder of 149 = 110001The Hexadecimal SystemA hexadecimal system based on power of the number 1616 symbols are used: 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,FExample: 7FA2 = (7x163) + (Fx162) + (Ax161) + (2x160) 7FA2 = 28672 + 3840 + 160 + 2 7FA2 = 32674The Hexadecimal System (2)Converting decimal to hexadecimal:Example: 127127/16 = 7 with a remainder of 15 (F)127 = 7FThe Hexadecimal System (3)Converting hexadecimal to binary by divide binary to 4 bit groups: Binary Dec Hexa 0000 0 0 0001 1 1 0010 2 2 0011 3 3 0100 4 4The Hexadecimal System (4) Binary Dec Hexa 0101 5 5 0110 6 6 0111 7 7 1000 8 8 1001 9 9The Hexadecimal System (5) Binary Dec Hexa 1010 10 A 1011 11 B 1100 12 C 1101 13 D 1110 14 E 1111 15 FThe Hexadecimal System (6)Example: 1101 1010 0100 0110 = DA46 C9F7 = 1100 1001 1111 0111IP AddressesAn IP (Internet Protocol) address is a unique identifier for a node or host connection on an IP network. An IP address is a 32 bit binary number usually represented as 4 decimal values, each representing 8 bits Range 0 to 255 (known as octets) separated by decimal pointsExample: 140.179.220.200 Unique addressing allows communication between end stations.Path choice is based on destination address.Location is represented by an addressIntroducing IP AddressesIP AddressingIP Addresses (2)Every IP address consists of two parts One identifying the Net ID (network identifier) One identifying the Host ID (host identifier) Host AddressesNetwork ID and Host IDsA Network ID is assigned to an organization by a global authorityHost IDs are assigned locally by a system administratorBoth the Network ID and the Host ID are used for routingIP Address Classes0NetID10110NetID1110Multicast AddressHostIDNetIDHostIDHostIDClassABCD8 bits8 bits8 bits8 bitsIP Address ClassesClass A:126 possible network ID 16.777.214 host IDs per network IDaddresses begin with 0xxx, or 1 to 126 decimal Class B:16384 possible network IDs65.534 host IDs per network IDaddresses begin with 10xx, or 128 to 191 decimal IP Address Classes (2)Class C:2 million possible network IDs(2.097.152)about 254 host IDs per network IDaddresses begin with 110x, or 192 to 223 decimalSpecial AddressesAddresses beginning with 01111111, or 127 decimal, are reserved for loop-back and for internal testing on a local machine ( ping 127.0.0.1) 10.0.0.0 – 10.255.255.255, 172.16.0.0 – 172.31.255.255, 192.168.0.0 – 192.168.255.255: unused Internet addressHost and Network AddressesA single network interface is assigned a single IP address called the host addressA host may have multiple interfaces, and therefore multiple host addressesHosts that share a network all have the same IP network address (the network ID)Host and Network Addresses (2)In the example, 140.179.220.200 is a Class B address so by default the Network part of the address (also known as the Network Address) is defined by the first two octets (140.179.x.x) and the Host part is defined by the last 2 octets (x.x.220.200)IP Broadcast and Network AddressesAn IP broadcast addresses ( that is send to all hosts on the network) has a host ID of all 1sAn IP address that has a host ID of all 0s is called a network address and refers to an entire networkSubnet MaskDefault subnet masks:Class A : 255.0.0.0 (11111111.00000000.00000000.00000000) Class B : 255.255.0.0 (11111111.11111111.00000000.00000000) Class C : 255.255.255.0 (11111111.11111111.11111111.00000000)Subnet Mask (2)Applying a subnet mask to an IP address to identify the NetID and HostIDThe network bits are presented by the 1s in the maskThe host bits are presented by the 0sPerforming a bitwise logical AND operation between the IP address and the subnet mask results in the Network Address ( also call Network Number)Subnet Mask (3)For example:10001100.10110011.11110000.11001000 (140.179.240.200 Class B IP Address)11111111.11111111.00000000.00000000 (255.255.000.000 Default Class B Subnet)--------------------------------------------------- mask10001100.10110011.00000000.00000000 (140.179.000.000 Network Address)Addressing Without SubnetsSubnet AddressingSubnet AddressesAn organization can subdivide it’s host address space into groups called subnetsTo create subnet address, administrator borrows some bits from host field 10NetIDSubnetIDHostIDSubnet MaskSubnets not in use—the defaultSubnet Mask Without SubnetsNetwork number extended by eight bitsSubnet Mask with SubnetsSubnet Mask with SubnetsNetwork number extended by ten bitsAn ExampleYou are assigned a Class C network number of 200.133.175.0 (apologies to anyone who may actually own this domain address). You want to utilize this network across multiple small groups within an organization. You can do this by subnetting that network with a subnet addressAn Example (2)We will break this network into 14 subnets of 14 nodes each. This will limit us to 196 nodes on the network instead of the 254 we would have without subnetting, but gives us the advantages of traffic isolation and security. To accomplish this, we need to use a subnet mask 4 bits long An Example (3)Recall that the default Class C subnet mask is 255.255.255.0 (11111111.11111111.11111111.00000000 binary)Extending this by 4 bits yields a mask of 255.255.255.240 (11111111.11111111.11111111.11110000 binary)An Example (4)This gives us 16 possible network numbers, 2 of which cannot be used:Subnet bits Network Number Host Addresses Broadcast Address 0000 200.133.175.0 Reserved None 0001 200.133.175.16 .17 thru .30 200.133.175.31 0010 200.133.175.32 .33 thru .46 200.133.175.47 An Example (5)Subnet bits Network Number Host Addresses Broadcast Address ............1101 200.133.175.208 209 thru .222 200.133.175.223 1110 200.133.175.224 225 thru .238 200.133.175.239 1111 200.133.175.240ReservedNoneProtocolProtocols are the rules and procedures for communicatingThree points to think about protocolsMany protocols, each has it sown advantages and restrictionsProtocols work at various OSI layers, the layer in which it works describes its functionSeveral may work together in a protocol stack or suite: Levels in protocol stack map or correspond to the layers of the OSI modelTCP/IPTransmission Control Protocol/ Internet Protocol Provides routable, enterprise networking protocolAccess to worldwide internetProtocols written for TCP/IP:SMTP , FTP, SNMP TCP/IP (2)The function of the TCP/IP protocol stack, or suite, is the transfer of information from one network device to another. In doing so, it closely maps the OSI reference model in the lower layers, and supports all standard physical and data link protocols TCP/IP (3)DNS (Domain Name System) is a system used in the Internet for translating names of domains and their publicly advertised network nodes into addressesWINS (Windows Internet Naming Service) is a Microsoft-developed standard for Microsoft Windows NT that automatically associates NT workstations with Internet domain namesTCP/IP (4)POP3 (Post Office Protocol) is an Internet standard for storing e-mail on a mail server until you can access it and download it to your computer. It allows users to receive mail from their inboxes using various levels of securityTCP/IP (5)SMTP (Simple Mail Transport Protocol) governs the transmission of e-mail over computer networks. It does not provide support for transmission of data other than plain textSNMP (Simple Network Management Protocol) is a protocol that provides a means to monitor and control network devices, and to manage configurations, statistics collection, performance and securityTCP/IP (6)FTP (File Transfer Protocol) is a reliable connection-oriented service that uses TCP to transfer files between systems that support FTPHTTP (Hypertext Transfer Protocol) is the Internet standard that supports the exchange of information on the World Wide Web, as well as on internal networks. It supports many different file types, including text, graphic, sound, and videoTCP/IP (7)Telnet is a standard terminal emulation protocol used by clients for the purpose of making remote terminal connections to Telnet server services; enables users to remotely connect to routers to enter configuration commandsTCP/IP (8)Ping (Packet Internet Groper) is a diagnostic utility used to determine whether a computer is properly connected to devicesTraceroute is a program that is available on many systems, and is similar to PING, except that traceroute provides more information than PINGSummaryThis topic examined:Common ProtocolsTCP/IP IP address and Subnetting