What is "rambutan"

Rambutan \Ram*bu"tan\ (r[a^]m*b[=oo]"t[a^]n), n. [Malay ramb[=u]tan, fr. rambut hair of the head.] (Bot.) A Malayan fruit produced by the tree Nephelium lappaceum, and closely related to the litchi nut. It is bright red, oval in shape, covered with coarse hairs (whence the name), and contains a pleasant acid pulp. Called also ramboostan.

n. 1 A tree, ''Nephelium lappaceum'', of Southeast Asia. 2 The fruit of this tree.

1. n. Malayan tree bearing spiny red fruit [syn: rambotan, rambutan tree, Nephelium lappaceum]

2. pleasantly acid bright red oval Malayan fruit covered with soft spines [syn: rambotan]

The rambutan (; taxonomic name: Nephelium lappaceum) is a medium-sized tropical tree in the family Sapindaceae. The name also refers to the fruit produced by this tree. The rambutan is native to Malay- Indonesian region, and other regions of tropical Southeast Asia. It is closely related to several other edible tropical fruits including the lychee, longan, and mamoncillo.

Rambutan is a family of encryption technologies designed by the Communications-Electronics Security Group (CESG), the technical division of the United Kingdom government's secret communications agency, GCHQ.

It includes a range of encryption products designed by CESG for use in handling confidential (not secret) communications between parts of the British government, government agencies, and related bodies such as NHS Trusts. Unlike CESG's Red Pike system, Rambutan is not available as software: it is distributed only as a self-contained electronic device (an ASIC) which implements the entire cryptosystem and handles the related key distribution and storage tasks. Rambutan is not sold outside the government sector.

Technical details of the Rambutan algorithm are secret. Security researcher Bruce Schneier describes it as being a stream cipher ( linear feedback shift register) based cryptosystem with 5 shift registers each of around 80 bits, and a key size of 112 bits. RAMBUTAN-I communications chips (which implement a secure X.25 based communications system) are made by approved contractors Racal and Baltimore Technologies/Zergo Ltd. CESG later specified RAMBUTAN-II, an enhanced system with backward compatibility with existing RAMBUTAN-I infrastructure. The RAMBUTAN-II chip is a 64-pin quad ceramic pack chip, which implements the electronic codebook, cipher block chaining, and output feedback operating modes (each in 64 bits) and the cipher feedback mode in 1 or 8 bits. Schneier suggests that these modes may indicate Rambutan is a block cipher rather than a stream. The three 64 bit modes operate at 88 megabits/second.