**Connected: An Internet Encyclopedia**

*2. BASIC BLOCK SIZE*

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### 2. BASIC BLOCK SIZE

2. BASIC BLOCK SIZE
The representation of all items requires a multiple of four bytes (or
32 bits) of data. The bytes are numbered 0 through n-1. The bytes
are read or written to some byte stream such that byte m always
precedes byte m+1. If the n bytes needed to contain the data are not
a multiple of four, then the n bytes are followed by enough (0 to 3)
residual zero bytes, r, to make the total byte count a multiple of 4.

We include the familiar graphic box notation for illustration and
comparison. In most illustrations, each box (delimited by a plus
sign at the 4 corners and vertical bars and dashes) depicts a byte.
Ellipses (...) between boxes show zero or more additional bytes where
required.

+--------+--------+...+--------+--------+...+--------+
| byte 0 | byte 1 |...|byte n-1| 0 |...| 0 | BLOCK
+--------+--------+...+--------+--------+...+--------+
|<-----------n bytes---------->|<------r bytes------>|
|<-----------n+r (where (n+r) mod 4 = 0)>----------->|

**Next:** 3. XDR DATA TYPES

**Connected: An Internet Encyclopedia**

*2. BASIC BLOCK SIZE*