Distinguishing & Differentiating Network Design Elements & Compounds, Using Common Protocols

NAC (Network Access Control) : NAC provides network security by setting the rules by which connections to a network are governed. Computers attempting to connect to a network are denied access unless they comply with rules including levels of antivirus protection, system updates, and so on...effectively weeding out those who would perpetuate malicious attacks. The client computer continues to be denied until it has been properly updated, which in some cases can be taken care of by the NAC solution automatically. This often requires some kind of preinstalled software (an agent) on the client computer, or the computer is scanned by the NAC solution remotely.

Virtulization : A workstation can have multiple operating systems installed on it but can run only one OS at a time but by running virtualization software same workstation can run Windows server along with windows 7 and Linux or any other operating system at the same time. This will allow a developer to test a code on various environments at the same time and he can also move code from one operating system to another with basic copy paste. Each virtual desktop will typically need full network access. Configuring permissions for each virtual desktop can be tricky for administrator. Remote administration often uses virtual desktop to work on a workstation without knowledge of user sitting on the workstation.

Cloud Computing : It is used to offer on-demand services it increase capabilities of a person's computer or an organization's network. Some cloud computing services are free like email services and some are paid services like data storage. Cloud computing services are generally broken down into three categories of services:

• Software as a Service (SaaS): when users access applications over the Internet that are provided by a third party it is SaaS. There is no need to install the application on the local computer mostly these services run with in web-browser. Example: webmail.

• Infrastructure as a Service (IaaS): A service that offers computer networking, storage, load balancing, routing, and VM hosting. More and more organizations are seeing the benefits of offloading some of their networking infrastructure to the cloud.

• Platform as a Service (PaaS): This service provide software solutions to organizations like apllication development in a virtual environment without the cost or administration of a physical platform. Its main use is for easy-to-configure operating systems and on-demand computing.

1.4 Implement and use common protocols

IPSec (Internet Protocol Security) : It authenticates and encrypts IP packets, effectively securing communications between the computers and devices that are used in VPN. IPsec operates at the Network Layer of the OSI model. It differs from SSH, SSL, and TLS in that it is the only protocol that does not operate within the upper layers of the OSI model. It can negotiate cryptographic keys and establish mutual. The two primary security services that are provided by IPSec are:

• Authentication Header (AH) : AH provides the authentication of the sender

• Encapsulating Security Payload : ESP provides encryption of the payload.

SNMP (Simple Network Management Protocol) : It enables monitoring of remote systems. There are three main parts of SNMP a manager, an agent, and a database of management information. The manager provides the interface between the human network manager and the management system. The agent provides the interface between the manager and the physical device(s) being managed. The manager and agent use a Management Information Base (MIB) and a set of commands to exchange information.

SSH (Secure Shell) : It is a protocol that can create a secure channel between two computers or network devices, enabling one computer or device to remotely control the other. It is commonly used on Linux and Unix systems, and nowadays also has widespread use on Windows clients. It uses public key cryptography to authenticate remote computers. One computer (the one to be controlled) runs the SSH daemon, while the other computer runs the SSH client and makes secure connections to the first computer (which is known as a server), as long as a certificate can be obtained and validated.

DNS(Domain Name System) : Resolves IP addresses to host names.

SSL (Secure Socket Layer) / TLS (Transport Layer Security) : These are cryptographic protocols that provide secure Internet communications such as web browsing, instant messaging, e-mail, and VoIP. These protocols rely on a PKI for the obtaining and validating of certificates. These are called Application Layer Protocol. Two types of keys are required when any two computers attempt to communicate with the SSL or TLS protocols: A public key and a session key. Asymmetric encryption is used to encrypt and share session keys, and symmetric encryption is used to encrypt the session data.

TCP/IP (Transmission Control Protocol/Internet Protocol) : It is suite of communications protocols used to connect hosts on the Internet. TCP/IP uses several protocols, the two main ones being TCP and IP. TCP/IP is built into the UNIX operating system and is used by the Internet, making it the de facto standard for transmitting data over networks. Even network operating systems that have their own protocols, such as Netware, also supportTCP/IP.

FTPS (FTP Secure) : FTPS uses SSL or TLS to make secure connections. FTPS can work in two modes: explicit and implicit. In explicit mode the FTPS client must explicitly request security from an FTPS server and then mutually agree on the type of encryption to be used. In implicit mode, there is no negotiation, and the client is expected to already know the type of encryption used by the server. In general, implicit mode is considered to be more secure than explicit mode.

SFTP (Secure FTP) : SFTP is the SSH File Transfer Protocol. It is an extension of the SSH protocol, which uses port 22. Contrast this with FTPS, which is FTP Secure or FTP-SSL, which uses port 443.

SCP (Secure Copy) : It is a way of transferring files securely between two hosts it utilizes SSH. It runs on port 22 by default.

ICMP (Internet Control Message Protocol) : The Internet Control Message Protocol (ICMP) protocol is classic example of a client server application. The ICMP server executes on all IP end system computers and all IP intermediate systems (i.e routers). The protocol is used to report problems with delivery of IP datagrams within an IP network. It can be sued to show when a particular End System (ES) is not responding, when an IP network is not reachable, when a node is overloaded, when an error occurs in the IP header information, etc. The protocol is also frequently used by Internet managers to verify correct operations of End Systems (ES) and to check that routers are correctly routing packets to the specified destination address.

IPv4 Vs Ipv6

1.5 Identify commonly used default network ports

NetBIOS (Network Basic Input/Output System) : NetBIOS, or Network Basic Input/Output System, allows for session-layer communication on the OSI model. NetBIOS is primarily concerned with two functions: naming and starting/stopping NetBIOS "sessions." Since NetBIOS is not actually a networking protocol (it's an API) it is not routable and therefore nodes are only visible to other nodes within the same subnet.