What is a Protocol? Network Protocol Definition
In networking, a specific set of rules are present for formatting and processing data which is known as a protocol. The common language for computers is referred to as network protocols. Different software and hardware may use by the computers within a network. The protocols help the software and hardware to communicate with each other.
Standardized protocols are considered as a common language that can be used by the computers just like two people from different regions of the world may not able to understand each other’s native language but even then they can communicate with each other with the help of a shared third language. If Internet Protocol (IP) is used by one computer and the second computer also uses the same then they can communicate but if both the computer doesn’t use the same protocol, then they will not be able to communicate.
For different types of processes, different protocols are present on the internet. OSI model layer discusses the protocols.
Layers of the OSI Model
OSI stands for Open Systems Interconnection model. It is an abstract representation that shows the working of the internet. It consists of 7 layers and every layer of the OSI model represents a different category of networking functions.
- Physical Layer – This layer helps to transmit raw bitstream above the physical medium.
- Datalink Layer – The format of data on the network is defined by the data link layer.
- Network Layer – The main function of this layer to decide that the data will take which physical path to travel.
- Transport Layer – This layer will transmit data by using transmission protocols such as TCP and UDP.
- Session Layer – It helps to maintain a connection. This layer is also used to control ports and sessions.
- Presentation Layer – This layer helps to ensure that the data should be in a usable format. It will also help in data encryption.
- Application Layer – This is the final layer which is also known as the Human-computer interaction layer. In this layer, the network services can be accessed by the applications.
The networking functions become possible because of protocols. For example – data routing can be done by Internet Protocol (IP) which further indicates data packets’ location and their destination. Network-to-network communication is possible by IP. Hence, IP is considered as the third layer of the OSI model or protocol that is the network layer. Transmission Control Protocol (TCP) is another example that ensures the transportation of data packets throughout the networks goes smoothly. Hence, TCP is considered as the fourth layer of protocol that is the transport layer.
Protocols That Run on the Network Layer
As mentioned above, the protocol layer that is responsible for routing is the network layer which is also considered as IP. But it is not referred to as the only network layer protocol.
- IPsec – This stands for Internet Protocol Security (IPsec) that helps to set encrypted and authenticated IP connections for the virtual private network (VPN). Technically IPsec is not considered a single protocol instead it is a collection of protocols that consist of Encapsulating Security Protocol (ESP), Authentication Header (AH), and Security Associations (SA).
- ICMP – The protocol that reports errors and helps to update status is called the Internet Control Message Protocol (ICMP). For example – if the packet is not delivered by the router then the ICMO message will be sent back to the packet’s source.
- IGMP – This stands for Internet Group Management Protocol (IGMP) that helps to set multiple network connections. The multicasting is set up by IGMP which means data packets are received by multiple computers directed at one IP address.
What Other Protocols Used on the Internet?
The most important protocols are mentioned below:
- TCP – Transport Layer Protocol (TCP) helps in reliable data delivery. It is mainly used with IP and both the protocols together referred to as TCP/IP.
- HTTP – This stands for Hypertext Transfer Protocol (HTTP). It is the foundation of the World Wide Web (www). It is the internet that a high number of users interact with. The data transferring between devices is done by HTTP. The OSI protocol model layer 7 named application layer is also consisting HTTP because it helps to arrange the data in a format that applications like browsers can use directly without any interpretation. The computer’s operating system is handled by the lower layer of the OSI model, not applications.
- HTTPS – Hypertext Transfer Protocol Secure (HTTPS) is the one that provides encryption and security of HTTP messages. The disadvantage with HTTP is that it does not provide encryption so hackers or attackers can easily intercept an HTTP message and read it.
- TLS/SSL – Transport Layer Security (TLS) or Secure Sockets Layer (SSL) is the HTTPS protocol that helps in encryption and security. TLS is the new version of SSL.
- UDP – This stands for User Datagram Protocol (UDP). It is a faster but not reliable option to TCP at the transport layer. Services such as video streaming and gaming use UDP where fast data delivery is paramount.
Protocols Used by the Routers
The most efficient network paths are discovered after using certain protocols of network routers to other routers. While transferring user data, these protocols are not used. Some crucial network routing protocols are:
- BGP – This stands for Border Gateway Protocol (BGP). In the protocol networks, it is considered as an application layer protocol that uses to broadcast which IP addresses they control. The routers are allowed by this information to decide which data packets of the networks need to pass through to reach their destinations.
- EIGRP – The Enhanced Interior Gateway Routing Protocol (EIGRP) is the protocol that helps to identify the distance between routers. Every router’s record of the best routes (routing table) is automatically updated by EIGRP and those updates are broadcasted to other routers within the network.
- OSPF – This stands for Open Shortest Path First (OSPF) protocol that helps to calculate efficient network routes that are based on a variety of factors like distance and bandwidth.
- RIP – The Routing Information Protocol (RIP) is one of the older routing protocols that help to identify distances between routers. It is also considered an application layer protocol.
How are Protocols Used in Cyber Attacks?
The attackers or hackers can majorly exploit the functioning of the networking protocols that compromise or overwhelm systems. Most protocols are used in distributed denial-of-service (DDoS) attacks. Several solutions are offered by Cloudflare to stop every type of cyber-attacks. The TCP handshake process is handled by Cloudflare in case of an SYN flood attack on the server’s behalf. This will help the server’s resources to never get overwhelmed by open TCP connections.