edu.umass.cs.nio.nioutils

Class RTTEstimator

java.lang.Object

edu.umass.cs.nio.nioutils.RTTEstimator

public class RTTEstimator
extends java.lang.Object

Author:

arun

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RTTEstimator.IPv4Prefix An IPv4 address and a netmask length in the standard CIDR notation.

Constructor Summary

Constructors

Constructor and Description
RTTEstimator()

Method Summary

Modifier and Type	Method and Description
static int	addrToInt(java.net.InetAddress address)
static int	addrToPrefixInt(java.net.InetAddress address)
static void	closest(java.net.InetSocketAddress sender, java.util.Map<java.net.InetAddress,java.lang.Long> nearestMap)
static org.json.JSONObject	getAmazonIPToRegionFile()
static java.util.Set<java.net.InetAddress>	getClosest(java.net.InetAddress clientAddr)
static long	getRTT(java.net.InetAddress address)
static void	main(java.lang.String[] args)
static long	ping(java.net.InetAddress address)
protected static java.util.concurrent.ConcurrentHashMap<java.lang.String,java.lang.String>	populateAWSIPToRegionMap()
static java.lang.String	print()
static void	record(java.net.InetAddress address) Relies on Java implementation of (typically) ICMP echo.
static long	record(java.net.InetAddress address, long rtt)

Methods inherited from class java.lang.Object

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

Constructor Detail

RTTEstimator

public RTTEstimator()

Method Detail

record

public static void record(java.net.InetAddress address)

Relies on Java implementation of (typically) ICMP echo.

Parameters:

address -

record

public static long record(java.net.InetAddress address,
                          long rtt)

Parameters:

address -

rtt -

Returns:

rtt in quartets.

getRTT

public static long getRTT(java.net.InetAddress address)

Parameters:

address -

Returns:

RTT recorded for /24 prefix of address if any, else -1.

ping

public static long ping(java.net.InetAddress address)
                 throws java.io.IOException

Parameters:

address -

Returns:

RTT to address via a blocking ping. The implementation is JVM and platform dependent.

Throws:

java.io.IOException

getAmazonIPToRegionFile

public static org.json.JSONObject getAmazonIPToRegionFile()
                                                   throws java.io.IOException,
                                                          org.json.JSONException

Returns:

AWS IP ranges as a JSON object

Throws:

java.io.IOException

org.json.JSONException

populateAWSIPToRegionMap

protected static java.util.concurrent.ConcurrentHashMap<java.lang.String,java.lang.String> populateAWSIPToRegionMap()

Returns:

IP-as-string to region map.

addrToInt

public static int addrToInt(java.net.InetAddress address)

Parameters:

address -

Returns:

Integer form of address

addrToPrefixInt

public static int addrToPrefixInt(java.net.InetAddress address)

Parameters:

address -

Returns:

Integer form of /24 prefix

print

public static java.lang.String print()

Returns:

String representation of bounded-size map; used only for instrumentation.

closest

public static void closest(java.net.InetSocketAddress sender,
                           java.util.Map<java.net.InetAddress,java.lang.Long> nearestMap)

Parameters:

sender -

nearestMap -

getClosest

public static java.util.Set<java.net.InetAddress> getClosest(java.net.InetAddress clientAddr)

Parameters:

clientAddr -

Returns:

The closest servers to clientAddr if any recorded.

main

public static void main(java.lang.String[] args)
                 throws java.net.UnknownHostException

Parameters:

args -

Throws:

java.net.UnknownHostException