drcl.inet.protocol.ospf
Class OSPF_QoS

java.lang.Object
  drcl.DrclObj
      drcl.comp.Component
          drcl.net.Module
              drcl.inet.Protocol
                  drcl.inet.protocol.Routing
                      drcl.inet.protocol.ospf.OSPF
                          drcl.inet.protocol.ospf.OSPF_QoS

All Implemented Interfaces:

java.lang.Cloneable, InetConstants, ObjectDuplicable, java.io.Serializable, UnicastRouting

public class OSPF_QoS

extends OSPF

QoS extension to OSPF. Mainly based on RFC 2676 QoS Routing Mechanisms and OSPF Extensions. Without explicit indication. The following reference is from RFC 2676.

As described in sec. 1, the purpose of the extension is to "Obtain the information needed to compute QoS paths and select a path capable of meeting the QoS requirements of a given request" In this QoS extension, We use two kinds of mechanism to calculate the QoS routes. One is the on-demand calculation modified from the standard Dijkstra's algorithm. The QoS considered here is bandwidth requirement. When doing the calculation, we only consider the link with avail. bw larger than the requirement.

The second mechanism is the precomputation approach. It calculates the routes to each destination and obtains the max. bw on route and the next hop info, which are recorded in the routing table. Because of the changes in the link metric, the precomputation needs to be done periodically or by event trigger. The dynamic changes in the link metrics would trigger the recalculation of all paths. However, this requires the cooperations of other signalling protocols such as RSVP or MPLS LDP. Hence, in the current stage, the extension does not handle the dynamics of metrics. We only left the interface for the future exploration.

The implementation does support equal-cost paths for multiple nexthops

See Also:

OSPF, Serialized Form

Nested Class Summary

Nested classes inherited from class drcl.comp.Component

Component.Locks

Field Summary

static int

DEBUG_QOS Redefine Debug level of handling timeout events.

Fields inherited from class drcl.inet.protocol.ospf.OSPF

area_list, DATABASE, debug, DEBUG_ACK, DEBUG_DETAIL, DEBUG_LSA, DEBUG_NEIGHBOR, DEBUG_REFRESH, DEBUG_SAMPLE, DEBUG_SEND, DEBUG_SPF, DEBUG_TIMEOUT, debug2, HELLO, LS_ACK, LS_REQUEST, LS_UPDATE, ospf_if_list, router_id

Fields inherited from class drcl.inet.protocol.Routing

queryPort, rtconfigPort

Fields inherited from class drcl.net.Module

address, downPort, PortGroup_DOWN, PortGroup_UP, timerPort, upPort

Fields inherited from class drcl.comp.Component

FLAG_COMPONENT_NOTIFICATION, FLAG_DEBUG_ENABLED, FLAG_DIRECT_OUTPUT_ENABLED, FLAG_ENABLED, FLAG_ERROR_ENABLED, FLAG_EVENT_ENABLED, FLAG_EXPOSED, FLAG_GARBAGE_DISPLAY_ENABLED, FLAG_GARBAGE_ENABLED, FLAG_HAS_EXPOSED_CHILD, FLAG_PORT_NOTIFICATION, FLAG_STARTED, FLAG_STOPPED, FLAG_TRACE_ENABLED, FLAG_UNDEFINED_START, id, infoPort, locks, name, parent, PortGroup_DEFAULT_GROUP, PortGroup_EVENT, PortGroup_SERVICE, Root, Trace_DATA, Trace_SEND

Fields inherited from interface drcl.inet.InetConstants

BYTE_MODE, DEFAULT_BANDWIDTH, DEFAULT_BUFFER_SIZE, DEFAULT_MTU, EVENT_ID_CHANGED_PORT_ID, EVENT_IDENTITY_ADDED, EVENT_IDENTITY_REMOVED, EVENT_IF_NEIGHBOR_DOWN, EVENT_IF_NEIGHBOR_UP, EVENT_IF_PORT_ID, EVENT_LINK_BROKEN, EVENT_LINK_BROKEN_PORT_ID, EVENT_MCAST_HOST_PORT_ID, EVENT_PKT_ARRIVAL, EVENT_PKT_ARRIVAL_PORT_ID, EVENT_RT_ENTRY_ADDED, EVENT_RT_ENTRY_MODIFIED, EVENT_RT_ENTRY_REMOVED, EVENT_RT_MCAST_CHANGED_PORT_ID, EVENT_RT_UCAST_CHANGED_PORT_ID, EVENT_VIF_NEIGHBOR_DOWN, EVENT_VIF_NEIGHBOR_UP, EVENT_VIF_PORT_ID, HOST_ENTRY_EXT, ID_CSL, MCAST_QUERY_PORT_ID, PACKET_MODE, PID_AODV, PID_DV, PID_DVMRP, PID_HELLO, PID_IGMP, PID_OSPF, PID_RSVP, PID_TCP, PID_UDP, SERVICE_CONFIGSW_PORT_ID, SERVICE_ID_PORT_ID, SERVICE_IF_PORT_ID, SERVICE_MCAST_PORT_ID, SERVICE_RT_PORT_ID, UCAST_QUERY_PORT_ID

Constructor Summary

OSPF_QoS()
Constructor.

Method Summary

int	bw2metric(double bw)
java.lang.String	info() Returns information regarding this component.
double	metric2bw(int metric) transfer the value of the TOS metric (16 bits) to bandwidth value, units: bits/sec, ref: sec3.2.1
protected void	ospf_lsdb_install(OSPF_LSA new_lsa, OSPF_LSA old_lsa, OSPF_Area area) Besides the normal operations, record the special metrics recorded in LSA for QoS path calculation
protected Router_LSA	ospf_make_router_lsa(OSPF_Area area) make router lsa pkt to describe its neighbor LSA which supports QoS may carry more than one tos metric
java.util.Vector	ospf_QoS_spf_on_demand_calculate(OSPF_Area area, int dest, double bw_) On-demand version of calculating a path satisying specified requirements to a destination.
protected void	ospf_QoS_spf_precompute(OSPF_Area area) Appendex A.
void	reset() Resets the component for being used anew.
void	set_dynamic_precompute_options(boolean options_) Set the bit whether to execute precomputation according to dynamic changes, In this example, received lsa # is the reference
void	set_periodical_precompute_options(boolean options_, int period) Set the bit whether to enable precomputation periodically
void	set_QoS_options(int options_) Set value of TOS type, either 40( for bw) or 48 (for delay)
void	show_QoS_ondemand_nexthop_by_bw(int dest, double bw_) given a destination and the required the bw, print the nexthops, on-demand version
void	show_QoS_options()
void	show_QoS_precompute_nexthop_by_bw(int dest, double bw_) given a destination and the required the bw, print the nexthops, precompute version
protected void	timeout(java.lang.Object evt_) Handling timeout event.

Methods inherited from class drcl.inet.protocol.ospf.OSPF

dataArriveAtDownPort, delayed_acknowledge, direct_acknowledge, duplicate, getDebugLevelNames, getName, inactivity_timer, lsa_receive, neighborDownEventHandler, neighborUpEventHandler, ospf_area_rt_install, ospf_dbdesc_seqnum_init, ospf_if_lookup_by_addr, ospf_install_candidate, ospf_lsa_flood, ospf_lsa_flood, ospf_lsa_has_link, ospf_lsdb_install, ospf_lsdb_install, ospf_lsdb_install, ospf_lsdb_lookup, ospf_message_broadcast, ospf_message_send, ospf_nexthop_calculation, ospf_possible_ack, ospf_route_add, ospf_router_lsa_flood, ospf_send_dbdesc, ospf_send_hello, ospf_send_lsreq, ospf_send_single_hello, ospf_set_area_id, ospf_spf_init, ospf_vertex_lookup, ospf_vertex_lookup, process, transit_vertex_rtable_install

Methods inherited from class drcl.inet.protocol.Routing

addRTEntry, addRTEntry, addRTEntry, addRTEntry, addRTEntry, addRTEntry, addRTEntry, graftRTEntry, graftRTEntry, graftRTEntry, pruneRTEntry, pruneRTEntry, pruneRTEntry, removeAllRTEntries, removeRTEntry, removeRTEntry, replaceRTEntry, replaceRTEntry, retrieveAllRTEntries, retrieveBestRTEntryDest, retrieveRTEntry, retrieveRTEntryDest, retrieveRTEntrySrc

Methods inherited from class drcl.inet.Protocol

broadcast, broadcast, broadcast, broadcast, broadcast, broadcast, createConfigSwitchPort, createIDChangedEventPort, createIDServicePort, createIFEventPort, createIFQueryPort, createLinkBrokenEventPort, createMcastHostEventPort, createMcastQueryPort, createMulticastRTChangedEventPort, createPktArrivalEventPort, createRTServicePort, createUcastQueryPort, createUnicastRTChangedEventPort, createVIFEventPort, forward, forward, forward, forward, forward, forward, idAddedEventHandler, idRemovedEventHandler, LinkBrokenEventHandler, mcastHostJoinEventHandler, mcastHostLeaveEventHandler, pktArrivalHandler, processOther, routeQueryHandler, routeQueryHandler, rtAddedEventHandler, rtModifiedEventHandler, rtRemovedEventHandler, vNeighborDownEventHandler, vNeighborUpEventHandler

Methods inherited from class drcl.net.Module

cancelTimeout, dataArriveAtUpPort, deliver, getAddress, removeDefaultDownPort, removeDefaultUpPort, removeTimerPort, setAddress, setTimeout, setTimeoutAt

Methods inherited from class drcl.comp.Component

_resume, _start, _stop, addComponent, addComponent, addEventPort, addEventPort, addForkPort, addPort, addPort, addPort, addPort, addPort, addPort, addPort, addPort, addServerPort, addServerPort, cancelFork, componentAdded, componentRemoved, connect, containsComponent, containsComponent, containsPort, debug, disconnectAll, disconnectAllPeers, disconnectAllPorts, drop, drop, error, error, expose, exposeEventPorts, exposePort, exposePort, exposePort, exposePort, exposePort, findAvailable, findAvailable, findAvailable, finishing, fork, forkAt, getAllComponents, getAllPorts, getAllPorts, getAllWiresInside, getAllWiresInsideOut, getAllWiresOut, getComponent, getComponentFlag, getComponentFlag, getContract, getContractHT, getContractHT, getDebugFlagsInBinary, getForkManager, getID, getParent, getPort, getPort, getRoot, getRuntime, getTime, iduplicate, isAncestorOf, isComponentNotificationEnabled, isContainer, isDebugEnabled, isDebugEnabledAt, isDirectlyRelatedTo, isDirectOutputEnabled, isEnabled, isErrorNoticeEnabled, isEventExportEnabled, isGarbageDisplayEnabled, isGarbageEnabled, isPortNotificationEnabled, isPortRemovable, isStarted, isStopped, isTraceEnabled, lock, notify, notifyAll, operate, portAdded, portRemoved, reboot, removeAll, removeAllComponents, removeAllPorts, removeAllPorts, removeComponent, removeComponent, removePort, removePort, removePort, resume, run, sduplicate, send, sendAt, setComponentFlag, setComponentFlag, setComponentNotificationEnabled, setContract, setDebugEnabled, setDebugEnabled, setDebugEnabledAt, setDebugEnabledAt, setDebugEnabledAt, setDirectOutputEnabled, setDirectOutputEnabled, setEnabled, setErrorNoticeEnabled, setErrorNoticeEnabled, setEventExportEnabled, setEventExportEnabled, setExecutionBoundary, setGarbageDisplayEnabled, setGarbageDisplayEnabled, setGarbageEnabled, setGarbageEnabled, setID, setID, setName, setPort, setPort, setPortNotificationEnabled, setPortRemovable, setRuntime, setTraceEnabled, setTraceEnabled, sleepFor, sleepUntil, stop, toString, unexpose, unlock, useLocalForkManager, useLocalForkManager, wait, yield

Methods inherited from class drcl.DrclObj

clone

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

DEBUG_QOS

public static final int DEBUG_QOS

Redefine Debug level of handling timeout events.

See Also:

Constant Field Values

Constructor Detail

OSPF_QoS

public OSPF_QoS()

Constructor.

Method Detail

timeout

protected void timeout(java.lang.Object evt_)

Description copied from class: OSPF

Handling timeout event. According to the timeout event which can be obtained from evt_, there are different handling functions.

Overrides:

timeout in class OSPF

Parameters:

evt_ - event object got from the timer port

info

public java.lang.String info()

Description copied from class: Component

Returns information regarding this component. Subclasses should override this method to provide useful information at run time.

Overrides:

info in class OSPF

reset

public void reset()

Description copied from class: Component

Resets the component for being used anew. All the internal variables must be set to the initial state. All the ports and child components are reset as well.

Overrides:

reset in class OSPF

set_QoS_options

public void set_QoS_options(int options_)

Set value of TOS type, either 40( for bw) or 48 (for delay)

show_QoS_options

public void show_QoS_options()

set_periodical_precompute_options

public void set_periodical_precompute_options(boolean options_,
                                              int period)

Set the bit whether to enable precomputation periodically

set_dynamic_precompute_options

public void set_dynamic_precompute_options(boolean options_)

Set the bit whether to execute precomputation according to dynamic changes, In this example, received lsa # is the reference

show_QoS_ondemand_nexthop_by_bw

public void show_QoS_ondemand_nexthop_by_bw(int dest,
                                            double bw_)

given a destination and the required the bw, print the nexthops, on-demand version

show_QoS_precompute_nexthop_by_bw

public void show_QoS_precompute_nexthop_by_bw(int dest,
                                              double bw_)

given a destination and the required the bw, print the nexthops, precompute version

ospf_make_router_lsa

protected Router_LSA ospf_make_router_lsa(OSPF_Area area)

make router lsa pkt to describe its neighbor LSA which supports QoS may carry more than one tos metric

Overrides:

ospf_make_router_lsa in class OSPF

ospf_lsdb_install

protected void ospf_lsdb_install(OSPF_LSA new_lsa,
                                 OSPF_LSA old_lsa,
                                 OSPF_Area area)

Besides the normal operations, record the special metrics recorded in LSA for QoS path calculation

Overrides:

ospf_lsdb_install in class OSPF

ospf_QoS_spf_on_demand_calculate

public java.util.Vector ospf_QoS_spf_on_demand_calculate(OSPF_Area area,
                                                         int dest,
                                                         double bw_)

On-demand version of calculating a path satisying specified requirements to a destination. return value: the nexthop list of the destination (interface from the src) Note that the type of elements in Vector is OSPF_SPF_vertex

ospf_QoS_spf_precompute

protected void ospf_QoS_spf_precompute(OSPF_Area area)

Appendex A. Pseudocode for the BF Based Pre-Computation Algorithm - assumes a hop-by-hop forwarding approach - does not handle equal cost multi-paths for simplicity - ***Note***: Here we only consider the bidirectional links. During the LSA exchange process, if we have received a LSA from a node, say A, we don't know its existence and would not calculate a route to it. Local Variable: - TT[n][h]: n:index in QoS_V_list; h:hop num storing the max. bw and the next hop info. to this node n in the hth iteration. After calculation TT will be stored in QoS_RT - S_prev: list of vertices that changed a bw value in the TT table in the previous iteration. - S_new: list of vertices that changed a bw value (in the TT table etc.) in the current iteration. Each link info. (n,m) is required during the computation can be obtained by first retrieve the router LSA from n check each LSA link in this router LSA and get the link info. To ensure the bidirection connectivity, we need to check the router LSA from m

metric2bw

public double metric2bw(int metric)

transfer the value of the TOS metric (16 bits) to bandwidth value, units: bits/sec, ref: sec3.2.1

bw2metric

public int bw2metric(double bw)