Understanding secure network devices and protocols forms a central aspect for anyone involved in cybersecurity or IT security.
This article intends to explain the different kinds of network devices, their functions, and the protocols that ensure secure communication. Examples are included with every section to help the readers relate these concepts to practical scenarios.
Secure Network Devices and Protocols
Repeaters and Hubs
Repeaters are networking devices used to regenerate the signal and amplify it, thereby increasing the distance the data would be transmitted. Hubs refer to simple network devices that connect various Ethernet devices so they can behave as if they are using one network segment.
Example: Office Network Expansion
In a huge office, the distance between the main server and some of the workstations is much greater than the length of the cable for Ethernet, which is 100 meters. A repeater is used along the middle to boost the signal so that reliable communication over the greater distance can take place. For small setups, hubs can be used where devices connect directly to a single hub. However, these are not very common anymore due to security issues.
Bridges
They were used to connect two or more network segments, filtering traffic and reducing collisions. They operate on the data link layer of the OSI model (Layer 2).
Example: Segmenting a Network
A university has an academic building and an administrative building. On each building resides a separate LAN. A bridge is implemented to connect the two. This decreases the amount of traffic on each network segment, thus enhancing performance. Also, it becomes easier to manage the access to network resources.
Switches
Switches are smarter than hubs; hence, they can switch data packets to specific devices instead of broadcasting to all their ports. They work at Layer 2 and can also work at Layer 3-that is, the network layer-for routing.
Example: Effective Handling of Data
Within an enterprise setting, multiple computers, printers, and servers are linked using a switch. When a worker on a network sends a document to the printer, the switch ensures data travels to only that printer to reduce unnecessary network traffic, hence making it more effective.
Network Taps
Taps are hardware devices that allow network monitoring without any impact on network performance. Many times, taps are deployed for security applications to capture data for analysis.
Example: Security Monitoring
A financial institution is using a network tap to monitor traffic between its internal network and the internet. This setup allows the security team to analyze data packets for suspicious activity without disrupting normal operations.
Routers
Routers are devices that forward data packets between diverse sets of networks. They operate at Layer 3 of the OSI model and are crucial to the process of routing traffic across the internet.
Example: Home Internet Setup
In a normal home network, a router connects the local network to the internet. The router assigns IP addresses to devices within the home and manages the flow of data in and out to ensure requests from those devices (like streaming video) are routed as efficiently as possible.
Modems
Modems are used to convert digital data from a computer into analog form to send the data over telephone lines. Conversely, they take incoming analog data from telephone lines and convert it into digital data for processing by a computer. They are necessary when anyone wants to connect to the Internet.
Example: Connecting to the Internet
A subscriber may sign up for a broadband service and be given a modem. That modem may connect to an ISP’s network and establish an active internet connection with the subscriber. The modem will ensure that data is passed accurately between the devices of the subscriber and the ISP.
DTE/DCE and CSU/DSU
These are Data Terminal Equipment (DTE) and Data Circuit-terminating Equipment (DCE), which are equipment used to control the transmission of data. Channel Service Unit/Data Service Unit (CSU/DSU) is used to connect the DTE with the digital circuit.
Example of Business Communication
Inside the corporate environment, the CSU/DSU connects the router (DTE) of the company with the telecommunication network (DCE). This provides reliable leased line communication without the loss of data.
Hardware Operation
Understanding how hardware works on a network enables effective management and troubleshooting. Each device has specific roles and functions that go into overall network performance.
Example: Network Performance Monitoring
As an IT administrator, one would use network management software to schedule regular checks of routers, switches, and other devices that keep the network running. This will help in identifying bottlenecks to keep the network running smoothly.
Secure Communications
Authentication Protocols and Frameworks
These protocols ensure that users and devices are actually who they claim to be. General protocols used include Kerberos, RADIUS, and TACACS+.
Example: Access to Corporate Network
An organization uses RADIUS to authenticate employees who log onto the corporate network remotely. That way, only authorized personnel can connect to the network, hence protecting sensitive data from unauthorized access.
Virtual Private Network
A VPN secures and encrypts a potentially insecure network connection, such as to the Internet. VPN allows clients to send and receive data between hosts across shared or public networks as if their computing devices were directly connected to the private network.
Example: Security for Working Remotely
Because of the COVID-19 pandemic, many employees had to work from home. The company granted VPN access to ensure that employees could securely access company resources and communicate without exposing sensitive information to possible threats.
Remote Access
Remote access technologies enable users to connect with a network from some other location. It includes VPNs, remote desktop applications, and access through a secure shell.
Example: IT Support
IT support uses remote desktop software in order to troubleshoot a computer that belongs to some other user. This will let him securely access the user’s system, detects some problem that may have occurred in it, and applies a solution without the need to physically be present.
Conclusion
Understanding secure network devices and protocols is the basic knowledge of any specialist working in cybersecurity and IT security. By understanding the role of different devices and protocols that make communication secure, one will be able to protect his or her network from any kind of threat.