SWAP

Ship-to-Ship/Shore Wireless Access Protocol

Proposed Protocol version 0.1

Preamble

We the Martechs of UNOLS, in order to form a more perfect network, insure bandwidth, provide for common security, promote general connections, and ensure the blessings of the internet to ourselves and our clients, do ordain and establish this Ship-to-Ship/Shore Wireless Access Protocol.

Goals:

Ship-to-ship networking

Coordinated operations amongst two or more ships is becoming common. Often the coordination requires the ability to transfer large amounts of data.

Until cheap, high-bandwidth, full-time internet is availible at sea to all parties concerned, low-cost short-range ship-to-ship alternatives are attractive.

Ship-to-shore networking, especially when not in home port

Most of us have dockside internet connections, for our own ships in our homeport. However connecting a visiting ship is often problematic. A no-hands, no-configuration, high-speed connection would be sweet.

Leveraging from the ship-to-ship scenario should reduce initial costs, overhead, and maintenance.

Voluntary compliance

This protocol is intended to be strictly voluntary. Anyone wishing to take advantage of the standardization is welcome to do so. Anyone wishing to pursue a more promising avenue, and share with the rest of us, is also welcome to do so.

Reasonable security

Security will possibily be the largest subject of discussion, oh boy.

Compatability

Ship-to-ship/shore communications, especially between different organizations, requires prior agreement on issues of compatablity. This entails choosing standards and identifying compatibilities for:

Communications medium

Sub-space, laser links, and very long phone cables stretching behind the ship aside, radio seems the likely candidate for ship-to-ship networking.

Licensing hassels can be avoided by staying in the unlicensed frequencies like 900 MHz, 2.4 GHz, 5 GHz. Typically, the higher frequencies have higher data rates, but less range and penetration. Off the shelf networking equipment exists for all of the above frequencies.

Hardware

Although I have seen a few 900 MHz radio modems, I am unfamiliar with them.

The current industry focus is on 2.4 and 5 GHz products in the form of 802.11b and 802.11a. See An Overview of 802.11a and 802.11b Products.

There seems to be at least two price catagories for this equipment: under $150 and under $1500. The cheaper market is composed of low cost Access Points that are designed to act as ... an access point for a bunch of laptops (and other wandering devices) to connect to the network via the 802.11 standards.

Examples of the more expensive market include:

Protocols

According to the 802.11 Task Group Update 802.11 comes in a, b, e, g, h, and i flavors, real or proposed. A and b already exist and some manufactures are putting out devices to the proposed g specification. As far as I can tell, all of these standards are for Access Points (connecting a laptop to the network) only, no bridging (connecting two or more network segments), no relaying.

Some of the low cost Access Points, such as the Linksys - WAP11 will also do bridging. I have not yet implemented a Linksys bridge, but have seen some flakeness in Access Point mode.

Both the Orinoco and the HyperLink use TurboCell when in bridge mode. I don't know what the Cisco or Linksys use.

Software

Configuration

Sharing a uniform hands-off configuration will make life such easyier.


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http://pigeon.shipops.orst.edu/swap last modifed: 04 March 2003 by Toby Martin toby@coas.oregonstate.edu