TAP vs SPAN: Their Pros and Cons

TAP (Test Access Point) and SPAN (Switched Port Analyzer) are two methods used to capture network traffic. They both have advantages and disadvantages, and understanding their pros and cons can help network administrators make informed decisions about which method to use. In this article, we will discuss what network TAPs and SPAN are and then compare the pros and cons of each method. Network TAP products from Dualcomm Technology will be also be briefly described for considerations by network administrators when they decide to use network TAPs for monitoring their networks.

What is a Network TAP?

A network TAP is usually a hardware device that copies data as it flows through a network cable. A typical Network TAP has two inline network ports and at least one monitor port. It sits inline with the network cable between two network devices and allows a monitoring device to capture and analyze the traffic without interrupting the flow of data between the two network devices. Network TAPs are commonly used in network analysis and troubleshooting, intrusion detection, and performance monitoring.

Advantages and Disadvantages of Network TAPs

Advantages:

• Complete Visibility: Network TAPs offer complete visibility into the traffic flowing through a network. They can capture both inbound and outbound traffic, including all layer 2 and layer 3 packets.
• No Packet Loss: Network TAPs operate passively as external devices and do not interfere with the data being handled within network switches. This means there is no risk of packet loss or delay due to lack of packet processing power of network switches, ensuring that all network traffic is captured accurately.
• Greater flexibility: Network taps can be used with any type of network infrastructure, including switches, routers, and firewalls.
• No Configuration Required: Network TAPs are plug-and-play devices that do not require any configuration or management for network switches. They are passive devices that do not affect network performance, making them easy to install and use.

Disadvantages:

• Higher Cost: Network TAPs are more expensive than SPAN ports because they are specialized devices that require additional hardware.
• Physical installation: Network taps require physical installation, which can be time-consuming and disruptive to network operations.

What is a SPAN?

A Switched Port Analyzer (SPAN) is a feature on a managed network switch that allows a network administrator to monitor traffic on a specific switch port. The network switch copies traffic from the source port and forwards it to the destination port where the monitoring device is connected. SPAN is a software-based solution that is built into most network switches, which makes it a cost-effective option for monitoring network traffic.

Advantages and Disadvantages of SPAN

Advantages:

• Cost-Effective: SPAN ports are built into most network switches, which makes them a cost-effective option for monitoring network traffic.
• Scalable: SPAN ports can be configured to monitor multiple ports simultaneously, making them scalable for larger networks.
• Remote Access: Because SPAN is a software-based solution, monitoring devices can be located remotely, providing greater flexibility for network administrators.

Disadvantages:

• Packet Loss: SPAN ports can cause packet loss or delay because they operate at the switch level and rely on the switch's processing power to copy and forward traffic.
• Incomplete Visibility: SPAN ports may not capture all traffic flowing through the network because they are configured to monitor specific ports. This means that traffic on non-monitored ports may be missed.
• Configuration Required: Configuring SPAN ports can be complex and time-consuming, especially for larger networks with multiple switches. Human errors may occur which could mess up the whole network.

Dualcomm's Network TAPs

In conclusion, both network TAPs and SPAN have their advantages and disadvantages when it comes to capturing network traffic. Network TAPs offer complete visibility with no packet loss or delay, but they can be more expensive and less scalable than SPAN. SPAN is a cost-effective and scalable solution, but it can cause packet loss and its configuration can be complicated and risky.

Dualcomm Technology is an innovative vendor of network TAPs that has been in business since 2005. Dualcomm network TAPs are designed to be extremely affordable, reliable, and easy to use, making them a popular choice for network administrators in various industries. Most of Dualcomm network TAPs are so affordable that they can substantiate alleviate the higher cost issue of using network TAPs for monitoring network traffic as mentioned above.

One of Dualcomm's most popular network TAPs is the ETAP-XG 10G network TAP. With patent-pending technology, ETAP-XG is designed to be flexible and versatile that allows it to be used with both copper and fiber links at a range of link speeds from 100Mbps to 10Gbps. This makes it a highly adaptable solution that can be used in a wide range of networking environments, from small businesses to large enterprises. Another key advantage of ETAP-XG is its affordability. Despite that it can be used as a 10G network TAP, ETAP-XG is priced at just under 1/10th of the prices of other 10G network TAPs on the market. This makes ETAP-XG an extremely cost-effective solution for network administrators who require 10G network traffic monitoring at a very lowe cost.

In addition to ETAP-XG, Dualcomm Technology offers a wide range of other network TAPs that are designed to meet the needs of network administrators in various industries. Specifically, the following network TAPs are listed below for network administrators or other related IT professionals to consider:

1) Portable network TAPs for trouble-shooting network issues: DCSW-1005PT,  ETAP-2003, ETAP-2205, ETAP-2105, and ETAP-2406. 

2) For permanent deployment in critical paths in a network: ETAP-1000, ETAP-3105, ETAP-5203 and DCP-1004/DCP-1004L. 

3) Zero, low latency network TAPs for use in real-time or delay/latency-sensitive industrial networks such as EtherCAT and PROFINET: ETAP-1000 and ETAP-2406.