Repository : ssh://git@open-mesh.org/doc

On branches: backup-redmine/2017-07-13,master

commit 94bb62078c0d0a88ad95138eb3ff3b13a6f43480 Author: Marek Lindner mareklindner@neomailbox.ch Date: Sat Mar 17 05:50:51 2012 +0000

doc: batman-adv/ELP: fix broken link and spell checkin

94bb62078c0d0a88ad95138eb3ff3b13a6f43480 batman-adv/ELP.textile | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/batman-adv/ELP.textile b/batman-adv/ELP.textile index 64b7d312..ee9a09c6 100644 --- a/batman-adv/ELP.textile +++ b/batman-adv/ELP.textile @@ -11,14 +11,14 @@ This approach was chosen for its simplicity during the protocol design phase and * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time.

-As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determening the overall path transmit qualities. +As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities.

h2. 1. Definitions

* Node - A mesh router which utilizes the B.A.T.M.A.N. protocol as specified in this document on at least one network interface. -* originator - A node broadcasting its own OGMs (see [[OGM]] for details) that is therefore addressable within the mesh network routing layer. It is uniquely identifiable by its originator address. [[/|B.A.T.M.A.N.-Advanced]] uses the MAC address of its primary hard interface. -* hard-interface - Network interface utilized by B.A.T.M.A.N. for its own ethernet frames. +* originator - A node broadcasting its own OGMs (see [[OGM]] for details) that is therefore addressable within the mesh network routing layer. It is uniquely identifiable by its originator address. [[batman-adv:Doc-overview|B.A.T.M.A.N.-Advanced]] uses the MAC address of its primary hard interface. +* hard-interface - Network interface utilized by B.A.T.M.A.N. for its own Ethernet frames. * sliding window - Sequence numbers are recorded in dedicated sliding windows until they are considered out-of­-range. Thus, such a sliding window always contains the set of recently received sequence numbers. The amount of sequence numbers recorded in the sliding window is used as a metric for the quality of detected links and paths. * Neighbor: An ELP sender within one hop distance (note, this is defined differently for the OGM protocol)

@@ -26,7 +26,7 @@ h2. 2. Conceptual Data Structures

h3. 2.1. Neighbor List

-* Neighbor Address: The ethernet source address of the received ELP message. +* Neighbor Address: The Ethernet source address of the received ELP message. * Originator Address: The originator address of the node. * Packet Count Window: * Current Window Sequence Number: @@ -55,7 +55,7 @@ Each node periodically (ELP interval) generates and broadcasts ELP messages for * Version: Set your internal compatibility version. * Originator Address: Set this field to the primary MAC address of this B.A.T.M.A.N. node. * Sequence number: On first broadcast set the sequence number to an arbitrary value and increment the field by one for each following broadcast. -* Interval: Set to the current ELP interval of this interface in milli seconds. The default interval is 500ms and it may be reconfigured during run-time. +* Interval: Set to the current ELP interval of this interface in milliseconds. The default interval is 500ms and it may be reconfigured during run-time. * Num Neigh: The number of neighbors that are announced with this message.

If this B.A.T.M.A.N. interface wants to announce neighboring nodes it should append a neighbor entry message for each neighbor to be announced and fill the "number of neighbors" field accordingly. @@ -103,7 +103,7 @@ h3. 3.2. Receiving Echo Location Messages (ELP) Upon receiving an ELP packet a node must perform the following preliminary checks before the packet is further processed:

* If the ELP contains a version which is different to the own internal version the message must be silently dropped (thus, it must not be further processed). -* If the sender address of the ELP message is an ethernet multicast (including broadcast) address the message must be silently dropped. +* If the sender address of the ELP message is an Ethernet multicast (including broadcast) address the message must be silently dropped. * If the destination address of the ELP message is a unicast address the message must be silently dropped. * If the originator address of the ELP message is our own the message must be silently dropped as this ELP message originated from this node. * If the ELP message has not been received from an out-of-sync neighbor interface (see section 3.5) and if the ELP message does not contain a newer sequence number (duplicate, out-of-order or out-of-range) the message must be silently dropped. @@ -183,7 +183,7 @@ For each ELP message having passed the preliminary checks the following actions

* The last seen time of this neighbor interface needs to be updated. * The last updated time of this neighbor interface needs to be updated. -* The ndp interval of this neighbor interface needs to be updated with the ndp interval set in the received ELP message. +* The elp interval of this neighbor interface needs to be updated with the elp interval set in the received ELP message. * The last received sequence number from this neighbor needs to be set to the sequence number of the received ELP message. * If the sequence number of the received ELP message is higher than the current window sequence number then: ** The window's current sequence number for this neighbor needs to be set to the sequence number of the received ELP message. @@ -212,12 +212,12 @@ Periodically all ELP windows must be shifted to the expected current sequence nu

More precisely, for any interface of a node towards any according, stored neighbor interface check whether:

-* The last updated time plus the ndp interval times of this neighbor interface times two is higher than the current time. +* The last updated time plus the elp interval times of this neighbor interface times two is higher than the current time.

If so, the following actions must be performed:

* The last updated time of this neighbor interface needs to be set to the current time minus the neighbor interface's ELP interval. -* The current window sequence number of this neighbor needs to be set to the expected sequence number (based on the current sequence number, the current time, the last updated time as well as the neighbor interface's ndp interval) minus one. The result always needs to be rounded down. +* The current window sequence number of this neighbor needs to be set to the expected sequence number (based on the current sequence number, the current time, the last updated time as well as the neighbor interface's elp interval) minus one. The result always needs to be rounded down. * The sliding window of the ELP message must be shifted (purged) to reflect the new upper and lower boundaries of the ranking range. * The new resulting link RQ value is calculated by counting all sequence numbers that are to be found in the adjusted sliding window. * The best link TQ needs to be updated.