Mais conteúdo relacionado



  1. What is Network Models?
  2. What is Network Models? 1. OSI Reference Model 2. TCP/IP Reference Model
  3. The 7 layers of the OSI model
  4. BASIS FOR COMPARISON TCP/IP MODEL OSI MODEL Expands To Transmission Control Protocol/ Internet Protocol Open system Interconnect Meaning It is a client server model used for transmission of data over the internet. It is a theoretical model which is used for computing system. Number Of Layers 4 Layers 7 Layers Developed by Department of Defense (DoD) ISO (International Standard Organization) Tangible Yes No Usage Mostly used Never used Obeys Horizontal approach Vertical approach Comparison Chart
  5. Which model is better, OSI or TCP/IP? • Thus, we can conclude that both models have their own advantages and disadvantages. • If someone is focusing on the proper documentation, specification, and modularization, they should prefer the OSI model over the TCP/IP model. • But if someone is focusing more on the implementation, reliability, and security of the network, they should prefer the TCP/IP model over the OSI model.
  6. Difference between TCP/IP and OSI Model TCP/IP OSI Model The full form of TCP/IP is Transmission Control Protocol/ Internet Protocol. The full form of OSI is Open Systems Interconnection. It is a communication protocol that is based on standard protocols and allows the connection of hosts over a network. It is a structured model which deals which the functioning of a network. In 1982, the TCP/IP model became the standard language of ARPANET. In 1984, the OSI model was introduced by the International Organisation of Standardization (ISO). It comprises of four layers: •Network Interface •Internet •Transport •Application It comprises seven layers: •Physical •Data Link •Network •Transport •Session •Presentation •Application It follows a horizontal approach. It follows a vertical approach. The TCP/IP is the implementation of the OSI Model. An OSI Model is a reference model, based on which a network is created. It is protocol dependent. It is protocol independent.
  7. What is Network Protocols?
  8. What is a network protocol? It is a set of rules for communications. In networking, a protocol is a standardized way of doing certain actions and formatting data so that two or more devices are able to communicate with and understand each other. Example: To understand why protocols are necessary, consider the process of mailing a letter. On the envelope, addresses are written in the following order: name, street address, city, state, and zip code. If an envelope is dropped into a mailbox with the zip code written first, followed by the street address, followed by the state, and so on, the post office won't deliver it. There is an agreed-upon protocol for writing addresses in order for the postal system to work. In the same way, all IP data packets must present certain information in a certain order, and all IP addresses follow a standardized format.
  9. What is Internet Protocol?
  10. What is the Internet Protocol (IP)? The Internet Protocol (IP) is a protocol, or set of rules, for routing and addressing packets of data so that they can travel across networks and arrive at the correct destination. Data traversing the Internet is divided into smaller pieces, called packets. IP information is attached to each packet, and this information helps routers to send packets to the right place. Every device or domain that connects to the Internet is assigned an IP address, and as packets are directed to the IP address attached to them, data arrives where it is needed. • Once the packets arrive at their destination, they are handled differently depending on which transport protocol is used in combination with IP. • The most common transport protocols are TCP and UDP.
  11. What is IP Address?
  12. What is an IP address? How does IP addressing work? An IP address stands for internet protocol address is a unique identifier assigned to a device or domain that connects to the Internet. Each IP address is a series of characters, such as ''. Via DNS resolvers, which translate human-readable domain names into IP addresses, users are able to access websites without memorizing this complex series of characters. An IP address allows computers to send and receive data over the internet. Each IP packet will contain both the IP address of the device or domain sending the packet and the IP address of the intended recipient, much like how both the destination address and the return address are included on a piece of mail.
  13. How this IP address is assigned? How automobile license plate numbers is assigned? How this IP address is assigned? • Users are assigned IP addresses by Internet service providers (ISPs). • ISPs obtain allocations of IP addresses from a local Internet registry (LIR) or National Internet Registry (NIR), or from their appropriate Regional Internet Registry (RIR):
  14. IP address structure IP address structure: IP addresses are displayed as a set of four digits- the default address may be Each number on the set may range from 0 to 255. Therefore, the total IP address range ranges from to • IP Address is a 32 bit binary address written as 4 numbers separated by dots. • The 4 numbers are called as octets where each octet has 8 bits. • The octets are divided into 2 components- Net ID and Host ID.
  15. IP address structure 1. Network ID represents the IP Address of the network and is used to identify the network. 2. Host ID represents the IP Address of the host and is used to identify the host within the network. IP Address Example- 00000001.10100000.00001010.11110000 (Binary Representation) OR (Decimal Representation)
  16. Types of IP address There are mainly four types of IP addresses: • Public, • Private, • Static • Dynamic. Types of Website IP Addresses Two types of website IP Addresses are 1) Share IP Address 2) Dedicated IP Address
  17. Types of IP address Type of IPAddress Description Public IP A public IP address is an address where one primary address is associated with your whole network. Private IP A private IP address is a unique IP number assigned to every device that connects to your home internet network. Dynamic IP Dynamic IP addresses always keep changing. It is temporary and are allocated to a device every time it connects to the web. Static IP Static IP address never changes, but it can be altered as part of routine network administration. Shared IP The IP address is not unique and it is shared with other websites. Dedicated IP Dedicated IP address is assigned uniquely to each website.
  18. Types of IP address 1. Static IPAddress- • Static IP Address is an IP Address that once assigned to a network element always remains the same. • They are configured manually. 2. Dynamic IPAddress- • Dynamic IP Address is a temporarily assigned IP Address to a network element. • It can be assigned to a different device if it is not in use. • DHCP or PPPoE assigns dynamic IP addresses.
  19. What are the types of IP Addressing?
  20. IP addressing There are two systems in which IP Addresses are classified- Classful Addressing- In Classful Addressing System, IP Addresses are organized into following 5 classes-
  21. Classes of IP Address Class of IP Address Total Number of IPAddresses 1st Octet Decimal Range Number of Networks available Hosts per network Default Subnet Mask Class A 231 1 – 126 27 – 2 224 – 2 Class B 230 128 – 191 214 216 – 2 Class C 229 192 – 223 221 28 – 2 Class D 228 224 – 239 Not defined Not defined Not defined Class E 228 240 – 254 Not defined Not defined Not defined
  22. Classless Inter-Domain Routing (CIDR) Sometimes called supernetting (in contrast to subnetting). • Representation: It is as also a 32-bit address, which includes a special number which represents the number of bits that are present in the Block Id. • a . b . c . d / n Where, n is number of bits that are present in Block Id / Network Id. Example:
  23. What are versions IP Address?
  24. Version of IP address Two types of IP addresses are 1)IPV4 and 2) IPV6. IPV4 IPv4 was the first version of IP. It was deployed for production in the ARPANET in 1983. Today it is the most widely used IP version. It is used to identify devices on a network using an addressing system. The IPv4 uses a 32-bit address scheme allowing to store 2^32 addresses, which is more than 4 billion addresses. To date, it is considered the primary Internet Protocol and carries 94% of Internet traffic. Following are the features of IPv4: • Connectionless Protocol • Allow creating a simple virtual communication layer over diversified devices • It requires less memory, and ease of remembering addresses • Already supported protocol by millions of devices • Offers video libraries and conferences
  25. Version of IP address IPV6 It is the most recent version of the Internet Protocol. Internet Engineer Taskforce initiated it in early 1994. The design and development of that suite is now called IPv6. This new IP address version is being deployed to fulfill the need for more Internet addresses. It was aimed to resolve issues which are associated with IPv4. With 128-bit address space, it allows 340 undecillion unique address space. Here are the features of IPv6: • Hierarchical addressing and routing infrastructure • Stateful and Stateless configuration • Support for quality of service (QoS) • An ideal protocol for neighboring node interaction
  26. IPv4 vs. IPv6 The fourth version of IP (IPv4 for short) was introduced in 1983. However, just as there are only so many possible permutations for automobile license plate numbers and they have to be reformatted periodically, the supply of available IPv4 addresses has become depleted. IPv6 addresses have many more characters and thus more permutations; however, IPv6 is not yet completely adopted, and most domains and devices still have IPv4 addresses.
  27. What happen to other version ? IPv1 IPv2 IPv3 IPv5
  28. What is an IP packet? • IP packets are created by adding an IP header to each packet of data before it is sent on its way. • An IP header is just a series of bits (ones and zeros), and it records several pieces of information about the packet, including the sending and receiving IP address. • IP headers also report: – Header length – Packet length – Time To Live (TTL), or the number of network hops a packet can make before it is discarded – Which transport protocol is being used (TCP, UDP, etc.) • In total there are 14 fields for information in IPv4 headers, although one of them is optional.
  29. What is TCP/IP? • The Transmission Control Protocol (TCP) is a transport protocol, meaning it dictates the way data is sent and received. • A TCP header is included in the data portion of each packet that uses TCP/IP. • Before transmitting data, TCP opens a connection with the recipient. • TCP ensures that all packets arrive in order once transmission begins. • Via TCP, the recipient will acknowledge receiving each packet that arrives. • Missing packets will be sent again if receipt is not acknowledged. • TCP is designed for reliability, not speed. • Because TCP has to make sure all packets arrive in order, loading data via TCP/IP can take longer if some packets are missing. • TCP and IP were originally designed to be used together, and these are often referred to as the TCP/IP suite. • However, other transport protocols can be used with IP.
  30. What is UDP/IP? • The User Datagram Protocol, or UDP, is another widely used transport protocol. • It's faster than TCP, but it is also less reliable. • UDP does not make sure all packets are delivered and in order, and it doesn't establish a connection before beginning or receiving transmissions.
  31. IP Address Classification Based on Operational Characteristics: According to operational characteristics, IP address is classified as follows: Broadcast addressing– The term ‘Broadcast’ means to transmit audio or video over a network. A broadcast packet is sent to all users of a local network at once. They do not have to be explicitly named as recipients. The users of a network can open the data packets and then interpret the information, carry out the instructions or discard it. This service is available in IPv4. The IP address commonly used for broadcasting is Unicast addressing– This address identifies a unique node on the network. Unicast is nothing but one-to-one data transmission from one point in the network to another. It is the most common form of IP addressing. This method can be used for both sending and receiving data. It is available in IPv4 and IPv6. Multicast IP addresses– These IP addresses mainly help to establish one-to-many communication. Multicast IP routing protocols are used to distribute data to multiple recipients. The class D addresses ( to define the multicast group. Anycast addressing– In anycast addressing the data, a packet is not transmitted to all the receivers on the network. When a data packet is allocated to an anycast address, it is delivered to the closest interface that has this anycast address.
  32. Differences between IPv4 and IPv6 Addresses Basis for differences IPv4 IPv6 Size of IP address IPv4 is a 32-Bit IP Address. IPv6 is 128 Bit IP Address. Addressing method IPv4 is a numeric address, and its binary bits are separated by a dot (.) IPv6 is an alphanumeric address whose binary bits are separated by a colon (:). It also contains hexadecimal. Number of header fields 12 8 Length of header filed 20 40 Checksum Has checksum fields Does not have checksum fields Example 2001:0db8:0000:0000:0000: ff00:0042:7879 Type of Addresses Unicast, broadcast, and multicast. Unicast, multicast, and anycast. Number of classes IPv4 offers five different classes of IP Address. Class A to E. lPv6 allows storing an unlimited number of IP Address.
  33. Configuration You have to configure a newly installed system before it can communicate with other systems. In IPv6, the configuration is optional, depending upon on functions needed. VLSM support IPv4 support VLSM (Variable Length Subnet mask). IPv6 does not offer support for VLSM. Fragmentation Fragmentation is done by sending and forwarding routes. Fragmentation is done by the sender. Routing Information Protocol (RIP) RIP is a routing protocol supported by the routed daemon. RIP does not support IPv6. It uses static routes. Network Configuration Networks need to be configured either manually or with DHCP. IPv4 had several overlays to handle Internet growth, which require more maintenance efforts. IPv6 support autoconfiguration capabilities. Best feature Widespread use of NAT (Network address translation) devices which allows single NAT address can mask thousands of non-routable addresses, making end-to-end integrity achievable. It allows direct addressing because of vast address Space.
  34. Address Mask Use for the designated network from host portion. Not used. SNMP SNMP is a protocol used for system management. SNMP does not support IPv6. Mobility & Interoperability Relatively constrained network topologies to which move restrict mobility and interoperability capabilities. IPv6 provides interoperability and mobility capabilities which are embedded in network devices. Security Security is dependent on applications – IPv4 was not designed with security in mind. IPSec(Internet Protocol Security) is built into the IPv6 protocol, usable with a proper key infrastructure. Packet size Packet size 576 bytes required, fragmentation optional 1208 bytes required without fragmentation Packet fragmentation Allows from routers and sending host Sending hosts only Packet header Does not identify packet flow for QoS handling which includes checksum options. Packet head contains Flow Label field that specifies packet flow for QoS handling DNS records Address (A) records, maps hostnames Address (AAAA) records, maps hostnames
  35. Address configuration Manual or via DHCP Stateless address autoconfiguration using Internet Control Message Protocol version 6 (ICMPv6) or DHCPv6 IP to MAC resolution Broadcast ARP Multicast Neighbour Solicitation Local subnet Group management Internet Group Management Protocol GMP) Multicast Listener Discovery (MLD) Optional Fields Has Optional Fields Does not have optional fields. But Extension headers are available. IPSec Internet Protocol Security (IPSec) concerning network security is optional Internet Protocol Security (IPSec) Concerning network security is mandatory Dynamic host configuration Server Clients have approach DHCS (Dynamic Host Configuration server) whenever they want to connect to a network. A Client does not have to approach any such server as they are given permanent addresses. Mapping Uses ARP(Address Resolution Protocol) to map to MAC address Uses NDP(Neighbour Discovery Protocol) to map to MAC address Combability with mobile devices IPv4 address uses the dot- decimal notation. That’s why it is not suitable for mobile networks. IPv6 address is represented in hexadecimal, colon- separated notation. IPv6 is better suited to mobile networks.