Introduction

IP Header Details

Every IP header has common fields of information. The layout of the information is always the same. Refer to the following diagram for a representation of the IP header.

Figure 1 —2 IP Header

Protocol

The protocol section is used to indicate the protocol being used by the transport layer. This could be TCP, UDP, or something else.

Time to live

The time to live section is used to prevent a frame from traversing the network forever. This field contains a number (maximum 255) that is set when the frame is originally generated. Each time the frame is passed through the bridge/router, the bridge/router will decrement the time to live by two. When the time to live reaches zero, the frame is discarded.

Header Checksum

The header checksum is used to verify the data in the IP header. The IP header checksum is recalculated each time a frame is passed through a router. The recalculation is necessary because the time to live field is changed.

Fragmentation

Fragmentation occurs when an IP frame must be split up into smaller IP frames. When the originating device generates the IP frame, the device is not aware of all the paths the frame must traverse to get to the destination device. If the IP frame is to pass through a network that has small packet capabilities, the IP frame must be split up and reassembled at the destination device. Each of the fragments is assigned a fragment offset value, which determines where the fragment fits into the original IP frame.

The P840 router will accept fragmented frames directed to itself and reassemble them, but it will not fragment frames.

Options

There are various options that may be set for any IP frame.

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Perle Systems P840 manual IP Header Details

P840 specifications

Perle Systems is renowned for its high-performance networking hardware, and the Perle P840 model exemplifies this reputation with its advanced features and technologies. Designed for small to medium-sized enterprises, the P840 serves as a versatile and reliable solution for connectivity needs.

One of the main features of the Perle P840 is its robust network performance, supporting both Ethernet and serial connectivity. With support for RS-232, RS-422, and RS-485 interfaces, the P840 enables seamless integration of legacy devices into modern network architectures, allowing businesses to leverage existing infrastructure without the need for extensive upgrades.

The P840 also boasts advanced security features to protect sensitive data during transmission. It supports SSL encryption and VPN capabilities, ensuring that data travels securely across the network. Additionally, it implements strong authentication protocols, providing organizations with peace of mind knowing that their communications are safeguarded against potential threats.

Another standout characteristic of the P840 is its flexibility in configuration. It offers multiple port configurations, allowing for customization based on specific user needs. With options for both managed and unmanaged modes, the device can easily adapt to various network environments. This flexibility makes it suitable for diverse applications, including industrial automation, process control, and telecommunications.

The Perle P840 is designed for durability and reliability, featuring a rugged enclosure that can withstand demanding environments. Its solid-state components reduce the risk of failure, contributing to increased uptime and lower maintenance costs. Furthermore, the compact design allows for easy installation in tight spaces, making it a practical choice for various deployment scenarios.

In terms of management and monitoring, the P840 includes an intuitive web-based interface, enabling administrators to configure settings and monitor network performance effortlessly. SNMP support further enhances management capabilities, allowing for integration into larger network management systems.

Overall, the Perle P840 stands out as a powerful solution for enterprises seeking seamless connectivity, robust security, and flexibility in configuration. Its combination of advanced features and durable design makes it an ideal choice for industries requiring reliable serial and network connectivity in challenging environments. With the P840, businesses can build a resilient networking infrastructure that supports their growing demands while safeguarding their critical data.