Browse Prior Art Database

Extending Nodes in a Network

IP.com Disclosure Number: IPCOM000041988D
Original Publication Date: 1984-Mar-01
Included in the Prior Art Database: 2005-Feb-03
Document File: 2 page(s) / 14K

Publishing Venue

IBM

Related People

Lindsay, BG: AUTHOR

Abstract

This invention relates to a method for extending nodes in a network in which all network nodes maintain a membership list. The method steps include (a) sending an invitation to join by a first node to a second node; (b) recording the message and either rejecting the invitation if the first node identity is not listed at the second node or accepting otherwise; and (c) if rejected, sending an invitation to the first node which accepts. In a distributed database environment, consisting of multiple database sites interacting over a communication network, it is important to be able to add a new database site to the distributed database network without requiring simultaneous system generation activity at all the sites of the distributed database system.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 51% of the total text.

Page 1 of 2

Extending Nodes in a Network

This invention relates to a method for extending nodes in a network in which all network nodes maintain a membership list. The method steps include (a) sending an invitation to join by a first node to a second node; (b) recording the message and either rejecting the invitation if the first node identity is not listed at the second node or accepting otherwise; and (c) if rejected, sending an invitation to the first node which accepts. In a distributed database environment, consisting of multiple database sites interacting over a communication network, it is important to be able to add a new database site to the distributed database network without requiring simultaneous system generation activity at all the sites of the distributed database system. This invention presents a method for easily extending the network of interworking database sites without shutting down any of the sites of the distributed database or requiring synchronized actions at the new and old sites of the database network. It is assumed that the distributed database network may be defined by logical, bilateral links between individual database sites. Users at any database site can access data (subject to database authorization checks) at any site which is linked to the database at the user's site. Attempts to access data at other (unlinked) sites will fail because no database site will attempt to access a remote site not in its list of linked sites. Additionally, all database sites will refuse to accept remotely generated access requests from any site not in their list of linked sites. These access restrictions between unlinked sites are necessary to prevent unauthorized intersite accesses and to preserve individual site autonomy. Establishment of a linkage between two sites is accomplished by "introducing" the two database sites. Each database must be introduced to the other before the linkage between the two sites is complete. A suitably authorized user at any site can introduce that site to any other site by executing the INTRODUCE command which is a statement in the data definition l...