IP address: What lies beneath?

IP address: What lies beneath?

Author: surender

An Internet Protocol (IP) address is a numerical identification and logical address that is assigned to devices participating in a computer network utilizing the Internet Protocol for communication between its nodes.

The original designers defined an IP address as a 32-bit number, now named as Internet Protocol Version 4 (IPv4), and are still in use today. However, due to the enormous growth of the Internet and the resulting depletion of the address space, a new addressing system (IPv6), using 128 bits for the address, was developed in 1995 and last standardized by RFC 2460 in 1998.

Although IP addresses are stored as binary numbers, they are usually displayed in human-readable notations, for e.g., 208.77.188.166 (for IPv4) and 2001:db8:0:1234:0:567:1:1 (for IPv6). The role of the IP address has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there." IP addresses are considered software addresses, and are not hard coded hardware addresses.

The Internet Assigned Numbers Authority (IANA) manages the IP address space allocations globally. IANA works in cooperation with five Regional Internet Registries (RIRs) to allocate IP address blocks to Local Internet Registries (Internet service providers) and other entities.

IP addresses are categorized into two categories:
2022 Private Addresses: These are addresses that are used on the private network, and which are not visible on the Internet. They are often used with network address translators to connect to the global public Internet.
2022 Public Addresses: These are Internet Assigned Numbers Authority (IANA) registered addresses which are visible on the Internet.

IP version 6 addresses
The next generation of the Internet Protocol, aimed to replace IPv4 and to expand the Internet's addressing capability on the Internet, was eventually named Internet Protocol Version 6 (IPv6). The address size was increased from 32 to 128 bits or 16 octets, which, even with a generous assignment of network blocks, is deemed sufficient for the foreseeable future.

Static and dynamic IP addresses
When a computer is configured to use the same IP address each time it powers up, this is known as a Static IP address. In contrast, in situations when the computer's IP address is assigned automatically, it is known as a Dynamic IP address.

IP Address Assignment Methods
IP addressing can occur through either of the following methods:
2022 Dynamically assigning IP addresses through Dynamic Host Configuration Protocol (DHCP): IP addresses that are assigned via a DHCP server are regarded as dynamically assigned IP addresses. The DHCP server assigns IP addresses from a predetermined IP address range(s).
2022 Manually assigning IP addresses: Manually assigning IP addresses can be time consuming, and can lead to duplicated IP address assignments. IP addressing normally occurs manually when there are no configured DHCP servers on the network and the network haves multiple network segments or a computer has a static IP addresses or the user configure computers on important network servers such as domain controllers, or DNS servers.
2022 Automatically assigning IP addresses through Automatic Private IP Addressing (APIPA): APIPA can be used as an alternative when no DHCP server exits to dynamically assign IP address. APIPA works well in smaller networks, when a computer is used on more than one network.


Special IP addresses:
A few IP addresses are reserved for specific special purposes. The reserved IP addresses are:
2022 Network segment of the address specified to zeros/0s: Indicates this network or subnet (local network).
2022 Network segment of the address specified to ones/1s: Indicates this network and all associated subnets.
2022 Network address 127: The address is reserved for loopback testing.
2022 Host address of all zeros/0s: The address is typically used in routing tables, and when referencing a network, but not particular hosts on the network.
2022 Host address of all ones/1s: This is used as a broadcast address for all the nodes on a particular network.

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Soridis introduces SUPRA, their new Alarm Supervision Software featuring Perle I/O Device Servers

Soridis introduces SUPRA, their new Alarm Supervision Software featuring Perle I/O Device Servers

Author: Perle Systems

SUPRA, Soridis’ new cutting-edge Alarm Supervision Software, allows railways to supervise all alerts on a rail network and monitor stations at both a local and regional level. SUPRA provides a complete graphic view of the network’s state and quicker troubleshooting through the setting of customised automatic alerts.

Every year, the French National Rail Infrastructure authority (RFF) invests more than € 2.5 billion in the national rail network, with further major investments by the National Railway Company (SNCF) and Paris’ own transportation services (RATP). In such a rapidly evolving market, the adaptability to new cutting-edge technologies is essential for all industry players, which are already re-designing the future of rail travel.
“We have been working with Perle for several years, for projects of such importance as the Infogare system. The solution that Perle provided proved to be perfectly adapted for this very sensitive application”, explains Serge Grouazel, Managing Director at Soridis. He continues, “When we had to source a supplier for our new Alarm Supervision Software, the choice of Perle’s I/O Device Server was an easy one.”

Perle’s Ethernet I/O Device Servers enable comprehensive access and control of remote digital I/O, analog I/O, pulse I/O, relays and temperature sensors as well as connections of remote serial equipment on any IP network. The IOLAN DS I/O Device Server has the ability to monitor environmental alarms, intrusion detection, relay contact closures and equipment failure. Through remote operator or application control, opening and closing of integrated relay contacts or activation of digital output signals can be incorporated into any response of a critical event.

Soridis is showcasing SUPRA during the International Railway Exhibition (SIFER) in Lille, from 26th to 28th May 2009.

About Perle Systems - www.perle.com
Perle Systems is a leading developer, manufacturer and vendor of high-reliability and richly featured serial to Ethernet networking products. These products are used to connect remote users reliably and securely to central servers for a wide variety of business applications. Product lines include Console Servers for Data Center Management, Terminal Servers, Device Servers, Ethernet I/O and Serial Cards. Perle distinguishes itself through extensive networking technology, depth of experience in major real-world network environments and long-term distribution and VAR channel relationships in major world markets. Perle has offices and representative offices in 11 countries in North America, Europe and Asia and sells its products through distribution and OEM/ODE channels worldwide.

About Soridis – www.soridis.com
Soridis specialises in the design and implementation of information management systems for the transportation services.

Infogare was designed for the SNCF Ile de France and provides the live display of train times in both normal and disrupted situations. SORIDIS was instrumental at every stage, from the design through to the implementation of the system and installations which started in 1995. SORIDIS guarantees the hardware and software maintenance and follows very high constraints of system availability. INFOGARE has become the reference as a Traveller’s Information System for the public transport authority of Paris and its region (STIF). INFOGARE ensures the monitoring of 4000 display monitors in more than 400 stations. INFOGARE monitors and refreshes the real-time information for more than 5700 trains a day, providing train times to over 2,500,000 travellers daily.

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Article Source: ArticlesBase.com - Soridis introduces SUPRA, their new Alarm Supervision Software featuring Perle I/O Device Servers