About Voice over IP (VoIP)

Establishing a Before voice traffic can pass between the voice ports over the network, the source IP

Sessionmust establish a TCP and UDP session with the destination IP node. Each session is uniquely identified by a source IP address, destination IP address, source port number, and destination port number. The source and destination node exchange the following call packets to establish a session:

Stage

Packet Transferred

Description

 

 

 

1

ACP Call Request

The voice port sends an ACP (Adjacent

 

 

Channel Protocol) Call Request to inform

 

 

the source IP node that it wishes to send

 

 

voice over the network to the destination

 

 

voice port.

 

 

 

 

Open UDP

When a voice port attempts to make a call,

 

 

the Source IP node opens a UDP channel.

 

 

 

2

TCP Call Request

To open a session, the source IP node sends a

 

 

TCP call request to the destination IP node.

 

 

 

 

TCP Call Accept

The destination IP node responds to the Call

 

 

Request by sending a Call Accept, and

 

 

establishes a TCP session.

 

 

 

Establishing a After opening a TCP and UDP session, the source node must establish an SoTCP

Connectionconnection with the destination IP node. Each TCP session support multiple connections or SVCs. A unique connection identifier identifies each connection multiplexed on a TCP session. The source and destination IP nodes exchange the following call packets to establish a connection:

Stage

Packet Transferred

Description

 

 

 

1

SoTCP Internal Call

The source IP node sends an internal

 

Request

SoTCP call request packet with the UDP

 

 

port number included, to the destination IP

 

 

node. The destination IP node examines the

 

 

facilities field in the header to determine

 

 

the presence of voice traffic. If voice traffic

 

 

is present, the destination IP node opens a

 

 

UDP channel.

 

 

The destination IP node uses the UDP port

 

 

number in the internal SoTCP call request

 

 

packet to identify the destination port for

 

 

UDP packets.

 

 

 

2

ACP Call Request

The destination IP node sends an ACP call

 

 

request to the remote voice port.

 

 

 

 

ACP Call Accept

To accept the call, the voice port responds

 

 

with an ACP Call accept packet.

 

 

 

6

Voice Over IP

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3Com S200 manual Stage Packet Transferred Description

S200 specifications

The 3Com S200 is a cutting-edge networking solution designed to meet the demands of small to medium-sized businesses. Renowned for its reliability and performance, this switch offers seamless integration and enhances network efficiency through advanced features and technologies.

One of the standout features of the 3Com S200 is its versatility. With a variety of ports ranging from 8 to 48, the switch provides ample connectivity options for various devices. This flexibility makes it an ideal choice for businesses aiming to expand their network without the need for extensive infrastructure changes. Built-in support for Power over Ethernet (PoE) enables users to connect and power devices such as IP phones and cameras, simplifying wiring and installation.

Performance is another key characteristic of the 3Com S200. Equipped with Layer 2 switching capabilities, the S200 allows for intelligent traffic management and efficient data handling. It supports advanced features like VLAN tagging, which facilitates network segmentation, improving security and performance. Additionally, the switch boasts a user-friendly interface that enables streamlined management, making network monitoring and configuration easily accessible even for non-technical staff.

The durability and reliability of the 3Com S200 are further enhanced by its robust design. Built to handle the rigors of a business environment, the switch features a fanless design for quiet operation, making it suitable for office use where noise may be an issue. With energy-efficient technology, the S200 not only minimizes power consumption but also contributes to cost savings over time.

Security is a priority for modern networks, and the 3Com S200 excels in this area. It offers features such as port security and access control lists to protect sensitive data and manage user access. Moreover, support for SNMP (Simple Network Management Protocol) facilitates proactive network management and monitoring, allowing businesses to address potential issues before they escalate.

In conclusion, the 3Com S200 stands out as a reliable, efficient, and secure networking solution. With its versatile port options, Layer 2 capabilities, user-friendly management interface, and robust security features, it is an excellent choice for businesses looking to enhance their network infrastructure. Whether scaling operations or optimizing current performance, the 3Com S200 provides the technology and reliability needed to thrive in today’s digital landscape.