Feature: Add "Magic Bit" to the FSS-000F (Simple Packet) format.

Make the FSS-000F (Simple Packet) format more generalized and flexible by allowing other payload formats than only formally supporting FSS-000E (Payload).

This adds a new optional "Magic Block" that is designated via the "Magic Bit", which is the third bit from the left.

This should make it easy to store the Simple Packet as a local file.
This should make it easier for routing to optimize processing of the packet by quickly identifying the packet.

The "Control Block" and the "Size Block" have static sizes and positions, which should make it easy to identify the "Magic Block".
The third bit should be checked and then the "Magic Block" should be checked when trying to quickly identify the packet type via the "Magic Block".

diff --git a/fll/specifications/fss/fss-000f.html b/fll/specifications/fss/fss-000f.html
index 647161bfb88afdb2a25f172718e6e2961157330c..0d97648f252adb748432080dbd5f2e1c11737e04 100644 (file)
--- a/fll/specifications/fss/fss-000f.html
+++ b/fll/specifications/fss/fss-000f.html
@@ -81,20 +81,30 @@
 
             <div class="section-content">
               <p class="p">
-                The version date of this specification is <code class="code">2023/11/14</code>.
+                The version date of this specification is <code class="code">2024/06/05</code>.
               </p>
               <p class="p">
-                This is a network packet format that contains <code class="code">fss-000e (Payload)</code> within it.
+                This is a network packet format that often contains <code class="code">fss-000e (Payload)</code> within it.
+              </p>
+              <p class="p">
+                The <strong class="strong">Magic Block</strong> when containing <code class="code">FSS-000e (Payload)</code> in the <strong class="strong">Payload Block</strong> is: <code class="code">11010010100111101111010000111110</code>.
+              </p>
+              <p class="p">
+                The <strong class="strong">Magic Block</strong> when containing unspecified plain text in the <strong class="strong">Payload Block</strong> is: <code class="code">00101110000001001101110001000010</code>.
+              </p>
+              <p class="p">
+                The <strong class="strong">Magic Block</strong> when containing unspecified binary data in the <strong class="strong">Payload Block</strong> is: <code class="code">00010101101001001111000000001000</code>.
               </p>
               <p class="p">
                 The Simple Packet structure is described in blocks, of which are structured in bytes.
               </p>
               <p class="p">
-                There are only three blocks in this format:
+                There are three or four blocks in this format:
               </p>
               <ol>
                 <li>Control Block.</li>
                 <li>Size Block.</li>
+                <li>Magic Block.</li>
                 <li>Payload Block.</li>
               </ol>
               <p class="p">
@@ -102,12 +112,13 @@
                 There exists only a single byte within the <strong class="strong">Control Block</strong> (8-bits).
                 Regardless of the endianness of the packet, leftmost bit is always the endianness bit.
                 The second bit following that endianness bit represents the <em class="em">string</em> or <em class="em">binary</em> bit.
+                The third bit following the endiannes bit represents the magic bit.
               </p>
               <p class="p">
                 Control Block Structure:
               </p><pre class="preserve">
-[ Endianness Bit ] [ String / Binary Bit ] [ Remaining 6 Bits (unused) ]
-[ size: 1 bit    ] [ size: 1 bit         ] [ size: 6 bits              ]
+[ Endianness Bit ] [ String / Binary Bit ] [ Magic Bit   ] [ Remaining 5 Bits (unused) ]
+[ size: 1 bit    ] [ size: 1 bit         ] [ size: 1 bit ] [ size: 5 bits              ]
 </pre>
               <p class="p">
                 The endianness bit designates whether or not the packet is in big endian or little endian format.
@@ -115,8 +126,12 @@
                 All <em class="em">binary</em> data within this packet, following the Control Block, must respect this endianness bit (including the <strong class="strong">Size Block</strong>).
               </p>
               <p class="p">
+                The magic bit designates whether or not the packet contains the optional <strong class="strong">Magic Block</strong>.
+                When the magic bit is not set, then there is no <strong class="strong">Magic Block</strong>.
+              </p>
+              <p class="p">
                 The <em class="em">string</em> or <em class="em">binary</em> bit, a value of 0 designates that the packet is in string format and a value of 1 designates that the packet is in <em class="em">binary</em> format.
-                While the packet might be considered to be in string format, it is technically always in <em class="em">binary</em> format due to the <strong class="strong">Control Block</strong> and <strong class="strong">Size Block</strong>.
+                While the packet might be considered to be in string format, it is technically always in <em class="em">binary</em> format due to the <strong class="strong">Control Block</strong>, the optional <strong class="strong">Magic Block</strong>, and <strong class="strong">Size Block</strong>.
                 This means that the <em class="em">binary</em> bit designating the packet as either a <em class="em">string</em> packet or a <em class="em">binary</em> packet is referring to whether or not the <strong class="strong">Payload Block</strong> is in <em class="em">string</em> or <em class="em">binary</em> format.
                 The <strong class="strong">Payload Block</strong> itself can contain <em class="em">binary</em> data even when in <em class="em">string</em> format as per <code class="code">FSS-000e (Payload)</code>.
               </p>
@@ -138,18 +153,34 @@
                 This size must exactly match the packet to be a valid packet.
                 The size represents number of bytes in the file.
                 The <strong class="strong">Control Block</strong> is 1 byte long and the <strong class="strong">Size Block</strong> is 4 bytes long, therefore the maximum available size of the entire <strong class="strong">Simple Packet</strong> structure is <code class="code">(2^32)-6</code>.
+                The <strong class="strong">Magic Block</strong> is 4 bytes long, therefore when the magic bit is set, then the maximum available size of the entire <strong class="strong">Simple Packet</strong> structure is <code class="code">(2^32)-9</code>.
               </p>
               <p class="p">
-
+                Magic Block Structure:
+              </p><pre class="preserve">
+[ Magic Block   ]
+[ size: 32 bits ]
+</pre>
+              <p class="p">
+                The <strong class="strong">Magic Block</strong>  is an unsigned 32-bit digit used to uniquely identify the packet.
+                The 32-bits are treated as endianless such that the left to right order of the bits is always the same for both big and little endian systems.
+                The <strong class="strong">Magic Block</strong>  is required when the magic bit is set and it must not exist when the magic bit is not set.
+              </p>
+              <p class="p">
+                This offers optimization in identifying the packet and its structure.
+                This is particularly useful for quick identification on the network such as via routers.
+                This is particularly useful for storing the packet as a file.
+                This is particularly unhelpful for security and privacy given that it helps quickly identify the packet.
               </p>
               <p class="p">
                 Payload Block Structure:
               </p><pre class="preserve">
-[ Payload Block        ]
-[ size: (2^32)-6 bytes ]
+[ Payload Block                                                ]
+[ size: (2^32)-5 bytes (or (2^32)-9 bytes if magic bit is set) ]
 </pre>
               <p class="p">
-                The <strong class="strong">Payload Block</strong> is not defined by this standard other than that it exists and should be in <code class="code">FSS-000e (Payload)</code> format.
+                The <strong class="strong">Payload Block</strong> is not defined by this standard other than that it exists and is suggested to be in <code class="code">FSS-000e (Payload)</code> format.
+                If the <strong class="strong">Magic Block</strong> is present and set to <code class="code">11010010100111101111010000111110</code>, then this is expected to be in <code class="code">FSS-000e (Payload)</code> format.
                 The <code class="code">FSS-000e (Payload)</code> may be represented in either <em class="em">string</em> format or <em class="em">binary</em> format.
                 The <code class="code">FSS-000e (Payload)</code> may contain multiple <em class="em">header</em>(s) but may only contain a single <em class="em">payload</em>.
                 With this in mind, it is recommended that only a single <em class="em">header</em> be supported in the <strong class="strong">Payload Block</strong>.
@@ -164,6 +195,12 @@
 [ Control Block ] [ Size Block                                  ] [ Payload Block         ]
 [ 0b10000000    ] [ 0b00000000 0b00000000 0b00000100 0b11010010 ] [ size: 1229 (1234 - 5) ]
 </pre>
+              <p class="p">
+                Example Packet Structure with Magic Bit:
+              </p><pre class="preserve">
+[ Control Block ] [ Size Block                                  ] [ Magic Block                                 ] [ Payload Block         ]
+[ 0b10100000    ] [ 0b00000000 0b00000000 0b00000100 0b11010010 ] [ 0b11010010 0b10011110 0b11110100 0b00111110 ] [ size: 1225 (1234 - 9) ]
+</pre>
             </div>
           </section>
         </main>