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Contents 1 Choosing a Server 1.1 IPs 2 Latency Testing Scripts (User Submitted) 2.1 Bash Script To Handle The Mac Ping Output Format 2.2 Perl Script 2.3 Powershell 2.4 Linux Shell Script 2.5 Using PingInfoView (Freeware, Windows Only) 3 Latency and its importance

Choosing a Server

VoIP.ms offers many different servers, but which one should you choose? To put it simple, you can use the server closest to your location. Although that doesn't mean that a server further from your location will not work accordingly. For example, if you are located in Chicago, but you wish to use our Washington server, you will usually get good results. This entirely depends on the path taken by your internet service provider among many other reasons. Although the right rule of thumb is to use the server closer to you.

Note: Make sure that your SIP/IAX device and your phone number are pointing to the same server. 

IPs

Latency Testing Scripts (User Submitted)

All the following scripts were produced by voip.ms users who felt others might also benefit from the output of their efforts. They were written over a span of Years and probably need adjusting before you use them, to cater for changes in servers over time and changes in policies (like not testing heavily subscribed servers which are not open to new registrations)

If you aren't satisfied that the scripts are safe or simply don’t like the way they syntactically appear, you can still manually ping a selection of servers and choose a server based on the best latency. The following scripts are essentially just wrappers around the ping command which support lists of servers to feed to ping and present the output in a readable format.

If you feel you have a simpler cleaner script that works for another platform or language, please do add it to this wiki via a support ticket.

Bash Script To Handle The Mac Ping Output Format

To make use of this script (1) save as a plain text file (2) set permissions on the file to executable (3) invoke script e.g. Save script below using your favourite editor as pingVoipMS.sh (2) chmod u+x pingVoipMS.sh (3) ./pingVoipMS.sh This is a bash 3.x script, so it also works in Linux, just change the ping packet loss field from 7 to 6 in the final loop below (or wherever the loss field is in your ping output format). Depending upon your distro curl might need to change to wget.

#!/bin/bash
# Ping several servers and display Latency, Jitter and Packet Loss
#      Usage: [-c <count>][-i <wait time>][-r test restricted servers][<server list file>]
#
# The optional server list text file should be formatted with one host name per line.
# The list of voip.ms servers is available at https://wiki.voip.ms/article/Choosing_Server
# If no args are supplied, this script will scrape a ping server list from voip.ms
#
USER_FILE=""
COUNT=3; INTERVAL=5; RESTRICTED=0
restrictedList=(atlanta.voip.ms chicago.voip.ms
                montreal.voip.ms montreal2.voip.ms montreal3.voip.ms montreal4.voip.ms
                newyork.voip.ms newyork4.voip.ms seattle.voip.ms
                toronto.voip.ms toronto2.voip.ms toronto3.voip.ms toronto4.voip.ms)

# Handle any passed in script arguments
while getopts c:i:r parm
do
    case $parm in
        c)count_opt=$OPTARG;;
        i)interval_opt=$OPTARG;;
        r)RESTRICTED=1;;
        *)echo -e "Invalid arg\nUsage:\t[ -c <count of ECHO_REQUESTs to Tx, default 3> ] \
                  \n\t[ -i <wait time (s) between datagrams, default 5> ]                \
                  \n\t[ -r ] Include restricted servers in latency test                  \
                  \n\t[FILE <ping server list> ]";exit 1;;
    esac
done

# Test if an option was specified and whether it's a +ve non-zero integer
[[ -n $count_opt    && ($count_opt =~ ^[[:digit:]]+$)    && $count_opt -gt 0 ]] &&
        COUNT=$count_opt
[[ -n $interval_opt && ($interval_opt =~ ^[[:digit:]]+$) && $interval_opt -gt 0 ]] &&
        INTERVAL=$interval_opt

shift $((OPTIND - 1))

# Validate supplied file (server list)
[[ -n $1 && ! (-f $1 && -r $1) ]] &&
        { echo "\"$1\" file does not exist or is not readable"; exit 1; }
[[ -n $1 && -f $1 && -r $1 ]] && USER_FILE="$1"

if [[ -n $USER_FILE ]]
then
# Bash 3.x in macOS does not support readarray, need to do cumbersome array loops instead
    while IFS= read -r servers; do
        serverList+=( "$servers" )
    done < <(grep -Eo '^\b[[:alpha:]]+?[[:alnum:]]\.voip\.ms\b$' "$USER_FILE" | \
             grep -v '^\s*#' | awk NF | sort)
else
# N.B. The script looks for the html boldface tags <b> </b> inside a bracket
# If the website alters and the parse fails, manually create the list and
# supply as a script arg (or perhaps update the parsing to work again :)
    while IFS= read -r servers; do
        serverList+=( "$servers" )
    done < <(curl -sm 10 https://wiki.voip.ms/article/Choosing_Server | \
             grep -E '(<b>[[:alpha:]]+?[[:alnum:]]\.voip\.ms</b>)'    | \
             tr "<>" " " | awk '{print $(NF-3)}' | sort                 )
fi

# Newer voip.ms clients can't register onto these over-subscribed servers
# Don't test the restricted list unless explicitly asked (with the -r cmd line option)
if [[ $RESTRICTED -eq 0 ]]
then
    for server in "${restrictedList[@]}"
    do
        ix=$(printf "%s\n" "${serverList[@]}" | grep -n "^${server}" | cut -d ":" -f1)
        while IFS= read -ra idx; do
            keys+=( "${idx[@]}" )
        done < <([[ $ix -gt 0 ]] && echo $((ix-1)))
    done
    for ((i=${#keys[@]} - 1; i >= 0; i--)); do unset "serverList[keys[i]]"; done
fi

if [[ ${#serverList[@]} -eq 0 ]]
then
    echo "No unrestricted Voip.ms servers could be found, please supply a server list"
    exit 1
fi

runTime=$((COUNT * INTERVAL * ${#serverList[@]}))

echo "PING will send $COUNT packet(s) with a wait of $INTERVAL sec(s) between each packet"
echo "Change the PING options by invoking this script with -c and/or -i, default \"-c 3 -i 5\""
echo "Over $((${#serverList[@]})) server(s) the estimated script Run Time will be $runTime seconds"
echo "================================================================"
printf "%-20s %-18s %7s %8s %6s   %s\n" "VoIP Server" "IP Address" "Latency" "Jitter" "Loss" "Countdown"
echo "================================================================  (seconds)"

for myLn in "${serverList[@]}"
do
     while IFS=$'\n' read -r pings; do
         pingList+=( "$pings" )
         printf "%-64s %5d   %2d/%-2d\n" "$pings" \
                "$((runTime - COUNT * INTERVAL * ${#pingList[@]}))" \
                "${#pingList[@]}" "${#serverList[@]}"
     done < <( ping -c "$COUNT" -i "$INTERVAL" -q "$myLn" | awk \
     '
        /^PING / {myH=$2}
        /^PING / {
            IP = substr($3,2,15)
            split(IP,myIP,")") }
        /packet loss/ {myPL=$7}
        /min\/avg\/max/ {
            split($4,myS,"/")
            printf("%-20s %-18s %7.3f %8.3f %6s\n",
                    myH, myIP[1], myS[2], myS[4], myPL ) }
     ' )
done

echo "================================================================"
echo -e "\nMost appropriate server listed in order of best latency\n"
echo "================================================================"
printf "%-20s %-18s %7s %8s %6s\n" "VoIP Server" "IP Address" "Latency" "Jitter" "Loss"
echo "================================================================"
printf "%s\n" "${pingList[@]}" | LC_ALL=C sort -n -k 3,3 -k 5,5 -k 4,4 | \
        awk '{printf("%s    \(%2d\)\n",$0, NR)}'
echo "================================================================"

Perl Script

Pings list of voip.ms servers round robin with optional output csv file.

   # usage ping_voip.ms.pl <number of times> <seconds in between> <output.csv>
   use Net::Ping;
   use Time::HiRes;
   use strict;
   
   # input list 
   my @hosts = qw(
       atlanta.voip.ms
       atlanta2.voip.ms
       chicago.voip.ms
       chicago2.voip.ms
       chicago3.voip.ms
       chicago4.voip.ms
       dallas.voip.ms
       denver.voip.ms
       denver2.voip.ms
       houston.voip.ms
       losangeles.voip.ms
       losangeles2.voip.ms
       newyork.voip.ms
       newyork2.voip.ms
       newyork3.voip.ms
       newyork4.voip.ms
       seattle.voip.ms
       seattle2.voip.ms
       seattle3.voip.ms
       tampa.voip.ms
       washington.voip.ms
       washington2.voip.ms
       montreal.voip.ms
       montreal2.voip.ms
       montreal3.voip.ms
       montreal4.voip.ms
       toronto2.voip.ms
       toronto3.voip.ms
       toronto4.voip.ms
       toronto.voip.ms
       london.voip.ms
   );
   
   $| = 1; #autoflush
   # High precision syntax (requires Time::HiRes)
   my $p = Net::Ping->new("icmp",1);
   $p->hires();
   my $max_name_length = (reverse sort { $a <=> $b } map { length($_) } @hosts)[0];
   my $count = 4; # number of times to ping
   my $interval = 5; # seconds between ping rounds
   my $output_file = "";
   my @data;
   
   # check for arguments
   my $num_args = @ARGV;
   if ($num_args >= 1) {$count = $ARGV[0];}
   if ($num_args >= 2) {$interval = $ARGV[1];}
   if ($num_args >= 3) {$output_file = $ARGV[2];}
   
   # check argument validity
   $0 =~ /^.*\\(.*)$/;
   my $script = $1;
   if ($count !~ /^\d+$/ or $interval !~ /^\d+$/) {die "Usage: $script <number of rounds> <seconds between rounds> <output.csv>\n";}
   if (length($output_file) > 0 and $output_file !~ /\.csv$/) {$output_file .= ".csv";}
   
   # main loop
   for my $i (1..$count)
   {
       sleep $interval unless $i == 1;
       print "Round $i\n";
       my $host_num=0;
       foreach my $host (@hosts)
       {
           (my $ret, my $duration, my $ip) = $p->ping($host);
           $ip =~ /(\d+)\.(\d+)\.(\d+)\.(\d+)/; 
           if ($ret)
           {
               printf("%*s [ip: %3s.%3s.%3s.%3s] is alive (%6.2f ms)\n", $max_name_length, $host, $1, $2, $3, $4, $duration*1000);
               $data[$host_num][$i]=$duration*1000;
           }
           else
           {
               printf("%*s [ip: %3s.%3s.%3s.%3s] is dead\n", $max_name_length, $host, $1, $2, $3, $4);
           }
           $host_num++;
       }
       print "\n";
   }
   $p->close();
   
   # if output file name given
   if (length($output_file)>0)
   {
       # print output to file
       open FILE, ">$output_file" or die "$!\n";
       
       # print column headers
       print FILE "Server\\Round";
       for my $i (1..$count)
       {
           print FILE ", $i";
       }
       print FILE ", Average\n";
       
       # print data
       my $i = 0;
       foreach my $host (@hosts)
       {
           print FILE "$host";
           my $sum = 0;
           for my $j (1..$count)
           {
               $sum += $data[$i][$j];
               printf FILE ", %8.4f",$data[$i][$j];
           }
           printf FILE ", %8.4f\n",$sum/$count;
           $i++;
       }
       
       close FILE;
       print "Data written to $output_file\n";
   }
   
   # print summary to screen
   my $i = 0;
   printf("%-*s Average (ms)\n", $max_name_length, "Server");
   foreach my $host (@hosts)
   {
       my $sum = 0;
       for my $j (1..$count)
       {
           $sum += $data[$i][$j];
       }
       printf("%-*s %8.4f\n", $max_name_length+1, $host, $sum/$count);
       $i++;
   }

Output:

   Round 1
       atlanta.voip.ms [ip: 174. 34.146.162] is alive ( 88.97 ms)
      atlanta2.voip.ms [ip:  72.  9.246.170] is alive ( 92.99 ms)
       chicago.voip.ms [ip: 208.100. 39. 52] is alive ( 49.70 ms)
      chicago2.voip.ms [ip: 208.100. 39. 53] is alive ( 59.76 ms)
      chicago3.voip.ms [ip: 208.100. 39. 54] is alive ( 59.53 ms)
      chicago4.voip.ms [ip: 208.100. 39. 55] is alive ( 49.73 ms)
        dallas.voip.ms [ip:  74. 54. 54.178] is alive ( 94.99 ms)
        denver.voip.ms [ip: 173.248.161. 90] is alive ( 94.05 ms)
       denver2.voip.ms [ip: 173.248.159.210] is alive ( 85.13 ms)
       houston.voip.ms [ip: 209. 62.  1.  2] is alive (102.87 ms)
    losangeles.voip.ms [ip:  96. 44.149.186] is alive ( 64.92 ms)
   losangeles2.voip.ms [ip:  96. 44.149.202] is alive ( 63.41 ms)
       newyork.voip.ms [ip:  74. 63. 41.218] is alive (131.75 ms)
      newyork2.voip.ms [ip: 107.  6. 67.236] is alive (120.64 ms)
      newyork3.voip.ms [ip: 107.  6. 67.237] is alive (120.49 ms)
      newyork4.voip.ms [ip: 107.  6. 67.238] is alive (111.43 ms)
       seattle.voip.ms [ip:  50. 23.160. 50] is alive ( 94.25 ms)
      seattle2.voip.ms [ip:  50. 23.160. 51] is alive ( 95.86 ms)
      seattle3.voip.ms [ip:  50. 23.160. 52] is alive ( 90.85 ms)
         tampa.voip.ms [ip:  68.233.226. 97] is alive (123.29 ms)
    washington.voip.ms [ip: 208. 43.234.226] is alive ( 98.71 ms)
   washington2.voip.ms [ip: 208. 43.234.227] is alive (101.19 ms)
      montreal.voip.ms [ip:  67.205. 74.184] is alive ( 81.82 ms)
     montreal2.voip.ms [ip:  67.205. 74.187] is alive ( 86.13 ms)
     montreal3.voip.ms [ip:  72. 55.168. 18] is alive ( 77.09 ms)
     montreal4.voip.ms [ip:  67.205. 74.179] is alive ( 96.18 ms)
      toronto2.voip.ms [ip: 184. 75.215.114] is alive (103.70 ms)
      toronto3.voip.ms [ip: 184. 75.215.146] is alive (131.27 ms)
      toronto4.voip.ms [ip: 184. 75.213.210] is alive (125.13 ms)
       toronto.voip.ms [ip: 184. 75.215.106] is alive (103.26 ms)
        london.voip.ms [ip:   5. 77. 36.136] is alive (152.77 ms)
   
   Round 2
       atlanta.voip.ms [ip: 174. 34.146.162] is alive ( 88.14 ms)
      atlanta2.voip.ms [ip:  72.  9.246.170] is alive ( 92.86 ms)
       chicago.voip.ms [ip: 208.100. 39. 52] is alive ( 50.03 ms)
      chicago2.voip.ms [ip: 208.100. 39. 53] is alive ( 59.44 ms)
      chicago3.voip.ms [ip: 208.100. 39. 54] is alive ( 59.33 ms)
      chicago4.voip.ms [ip: 208.100. 39. 55] is alive ( 50.22 ms)
        dallas.voip.ms [ip:  74. 54. 54.178] is alive ( 95.58 ms)
        denver.voip.ms [ip: 173.248.161. 90] is alive ( 95.94 ms)
       denver2.voip.ms [ip: 173.248.159.210] is alive ( 85.29 ms)
       houston.voip.ms [ip: 209. 62.  1.  2] is alive (102.73 ms)
    losangeles.voip.ms [ip:  96. 44.149.186] is alive ( 65.59 ms)
   losangeles2.voip.ms [ip:  96. 44.149.202] is alive ( 64.27 ms)
       newyork.voip.ms [ip:  74. 63. 41.218] is alive (112.74 ms)
      newyork2.voip.ms [ip: 107.  6. 67.236] is alive (121.22 ms)
      newyork3.voip.ms [ip: 107.  6. 67.237] is alive (121.34 ms)
      newyork4.voip.ms [ip: 107.  6. 67.238] is alive (110.75 ms)
       seattle.voip.ms [ip:  50. 23.160. 50] is alive ( 94.06 ms)
      seattle2.voip.ms [ip:  50. 23.160. 51] is alive ( 95.33 ms)
      seattle3.voip.ms [ip:  50. 23.160. 52] is alive ( 91.58 ms)
         tampa.voip.ms [ip:  68.233.226. 97] is alive (122.94 ms)
    washington.voip.ms [ip: 169.62.41.189] is alive ( 98.28 ms)
   washington2.voip.ms [ip: 169.62.41.187] is alive (101.40 ms)
      montreal.voip.ms [ip:  67.205. 74.184] is alive ( 81.91 ms)
     montreal2.voip.ms [ip:  67.205. 74.187] is alive ( 85.64 ms)
     montreal3.voip.ms [ip:  72. 55.168. 18] is alive ( 75.15 ms)
     montreal4.voip.ms [ip:  67.205. 74.179] is alive ( 96.79 ms)
      toronto2.voip.ms [ip: 184. 75.215.114] is alive (103.10 ms)
      toronto3.voip.ms [ip: 184. 75.215.146] is alive (150.85 ms)
      toronto4.voip.ms [ip: 184. 75.213.210] is alive (138.40 ms)
       toronto.voip.ms [ip: 184. 75.215.106] is alive (103.45 ms)
        london.voip.ms [ip:   5. 77. 36.136] is alive (170.79 ms)
   
   Round 3
       atlanta.voip.ms [ip: 174. 34.146.162] is alive ( 88.76 ms)
      atlanta2.voip.ms [ip:  72.  9.246.170] is alive ( 92.86 ms)
       chicago.voip.ms [ip: 208.100. 39. 52] is alive ( 49.65 ms)
      chicago2.voip.ms [ip: 208.100. 39. 53] is alive ( 60.01 ms)
      chicago3.voip.ms [ip: 208.100. 39. 54] is alive ( 59.05 ms)
      chicago4.voip.ms [ip: 208.100. 39. 55] is alive ( 49.53 ms)
        dallas.voip.ms [ip:  74. 54. 54.178] is alive ( 95.82 ms)
        denver.voip.ms [ip: 173.248.161. 90] is alive ( 95.02 ms)
       denver2.voip.ms [ip: 173.248.159.210] is alive ( 85.60 ms)
       houston.voip.ms [ip: 209. 62.  1.  2] is alive (103.35 ms)
    losangeles.voip.ms [ip:  96. 44.149.186] is alive ( 65.79 ms)
   losangeles2.voip.ms [ip:  96. 44.149.202] is alive ( 64.05 ms)
       newyork.voip.ms [ip:  74. 63. 41.218] is alive (113.01 ms)
      newyork2.voip.ms [ip: 107.  6. 67.236] is alive (121.41 ms)
      newyork3.voip.ms [ip: 107.  6. 67.237] is alive (122.23 ms)
      newyork4.voip.ms [ip: 107.  6. 67.238] is alive (110.62 ms)
       seattle.voip.ms [ip:  50. 23.160. 50] is alive ( 93.65 ms)
      seattle2.voip.ms [ip:  50. 23.160. 51] is alive ( 95.19 ms)
      seattle3.voip.ms [ip:  50. 23.160. 52] is alive ( 90.75 ms)
         tampa.voip.ms [ip:  68.233.226. 97] is alive (125.12 ms)
    washington.voip.ms [ip: 208. 43.234.226] is alive ( 98.19 ms)
   washington2.voip.ms [ip: 208. 43.234.227] is alive (101.98 ms)
      montreal.voip.ms [ip:  67.205. 74.184] is alive ( 80.16 ms)
     montreal2.voip.ms [ip:  67.205. 74.187] is alive ( 87.16 ms)
     montreal3.voip.ms [ip:  72. 55.168. 18] is alive ( 76.54 ms)
     montreal4.voip.ms [ip:  67.205. 74.179] is alive ( 97.51 ms)
      toronto2.voip.ms [ip: 184. 75.215.114] is alive (104.18 ms)
      toronto3.voip.ms [ip: 184. 75.215.146] is alive (142.81 ms)
      toronto4.voip.ms [ip: 184. 75.213.210] is alive (138.95 ms)
       toronto.voip.ms [ip: 184. 75.215.106] is alive (103.78 ms)
        london.voip.ms [ip:   5. 77. 36.136] is alive (153.14 ms)
   
   Round 4
       atlanta.voip.ms [ip: 174. 34.146.162] is alive ( 89.19 ms)
      atlanta2.voip.ms [ip:  72.  9.246.170] is alive ( 92.98 ms)
       chicago.voip.ms [ip: 208.100. 39. 52] is alive ( 49.21 ms)
      chicago2.voip.ms [ip: 208.100. 39. 53] is alive ( 60.50 ms)
      chicago3.voip.ms [ip: 208.100. 39. 54] is alive ( 59.68 ms)
      chicago4.voip.ms [ip: 208.100. 39. 55] is alive ( 50.18 ms)
        dallas.voip.ms [ip:  74. 54. 54.178] is alive ( 93.93 ms)
        denver.voip.ms [ip: 173.248.161. 90] is alive ( 94.22 ms)
       denver2.voip.ms [ip: 173.248.159.210] is alive ( 85.10 ms)
       houston.voip.ms [ip: 209. 62.  1.  2] is alive (103.67 ms)
    losangeles.voip.ms [ip:  96. 44.149.186] is alive ( 65.58 ms)
   losangeles2.voip.ms [ip:  96. 44.149.202] is alive ( 63.60 ms)
       newyork.voip.ms [ip:  74. 63. 41.218] is alive (114.76 ms)
      newyork2.voip.ms [ip: 107.  6. 67.236] is alive (120.44 ms)
      newyork3.voip.ms [ip: 107.  6. 67.237] is alive (121.05 ms)
      newyork4.voip.ms [ip: 107.  6. 67.238] is alive (110.51 ms)
       seattle.voip.ms [ip:  50. 23.160. 50] is alive ( 94.04 ms)
      seattle2.voip.ms [ip:  50. 23.160. 51] is alive ( 96.92 ms)
      seattle3.voip.ms [ip:  50. 23.160. 52] is alive ( 91.23 ms)
         tampa.voip.ms [ip:  68.233.226. 97] is alive (123.28 ms)
    washington.voip.ms [ip: 208. 43.234.226] is alive ( 98.45 ms)
   washington2.voip.ms [ip: 208. 43.234.227] is alive (100.94 ms)
      montreal.voip.ms [ip:  67.205. 74.184] is alive ( 82.33 ms)
     montreal2.voip.ms [ip:  67.205. 74.187] is alive ( 85.02 ms)
     montreal3.voip.ms [ip:  72. 55.168. 18] is alive ( 76.85 ms)
     montreal4.voip.ms [ip:  67.205. 74.179] is alive ( 96.32 ms)
      toronto2.voip.ms [ip: 184. 75.215.114] is alive (104.22 ms)
      toronto3.voip.ms [ip: 184. 75.215.146] is alive (148.33 ms)
      toronto4.voip.ms [ip: 184. 75.213.210] is alive (141.61 ms)
       toronto.voip.ms [ip: 184. 75.215.106] is alive (105.91 ms)
        london.voip.ms [ip:   5. 77. 36.136] is alive (152.85 ms)
   
   Server              Average (ms)
   atlanta.voip.ms       88.7630
   atlanta2.voip.ms      92.9233
   chicago.voip.ms       49.6477
   chicago2.voip.ms      59.9305
   chicago3.voip.ms      59.3972
   chicago4.voip.ms      49.9152
   dallas.voip.ms        95.0790
   denver.voip.ms        94.8077
   denver2.voip.ms       85.2797
   houston.voip.ms      103.1562
   losangeles.voip.ms    65.4693
   losangeles2.voip.ms   63.8347
   newyork.voip.ms      118.0643
   newyork2.voip.ms     120.9265
   newyork3.voip.ms     121.2778
   newyork4.voip.ms     110.8275
   seattle.voip.ms       93.9993
   seattle2.voip.ms      95.8267
   seattle3.voip.ms      91.1035
   tampa.voip.ms        123.6570
   washington.voip.ms    98.4065
   washington2.voip.ms  101.3774
   montreal.voip.ms      81.5525
   montreal2.voip.ms     85.9863
   montreal3.voip.ms     76.4058
   montreal4.voip.ms     96.7013
   toronto2.voip.ms     103.7986
   toronto3.voip.ms     143.3156
   toronto4.voip.ms     136.0254
   toronto.voip.ms      104.1012
   london.voip.ms       157.3885

Powershell

Dec 2017 - A bug in the code shown washington2.voip.ms as the best server, this was corrected.

# Usage: Copy and paste the following code into a powershell window
# To run it from a command prompt, save this file with extension ps1. 
# Then run Powershell.exe -file "pathtothisscript.ps1"
Clear-Variable best* -Scope Global #Clear the best* variables in case you run it more than once...
#Get the list of servers into an array
$Servers =      
@("amsterdam.voip.ms","atlanta.voip.ms","atlanta2.voip.ms","chicago.voip.ms","chicago2.voip.ms","chicago3.voip.ms",
"chicago4.voip.ms","dallas.voip.ms","dallas2.voip.ms","denver.voip.ms","denver2.voip.ms","houston.voip.ms",
"houston2.voip.ms","london.voip.ms","losangeles.voip.ms","losangeles2.voip.ms","montreal.voip.ms",
"montreal2.voip.ms","montreal3.voip.ms","montreal4.voip.ms","montreal5.voip.ms","montreal6.voip.ms","montreal7.voip.ms",
"montreal8.voip.ms","newyork.voip.ms","newyork2.voip.ms","newyork3.voip.ms","newyork4.voip.ms","newyork5.voip.ms",
"newyork6.voip.ms","newyork7.voip.ms","newyork8.voip.ms","paris.voip.ms","sanjose.voip.ms","sanjose2.voip.ms",
"seattle.voip.ms","seattle2.voip.ms","seattle3.voip.ms","tampa.voip.ms","tampa2.voip.ms","toronto.voip.ms",
"toronto2.voip.ms","toronto3.voip.ms","toronto4.voip.ms","toronto5.voip.ms","toronto6.voip.ms","toronto7.voip.ms",
"toronto8.voip.ms","vancouver.voip.ms","vancouver2.voip.ms","washington.voip.ms","washington2.voip.ms")
$k = 0 #Counting variable so we know what server number we are testing
#num of servers to test
$servercount = $servers.length 
#Do the following code for each server in our array
ForEach($server in $servers)
{  
  #Add one to the counting variable....we are on server #1...then server 2, then server 3 etc...
  $k++
  #Update the progress bar                    
  Write-Progress -Activity "Testing Server: ${server}" -status "Testing Server $k out of $servercount" -percentComplete ($k / $servercount*100) 
  #Counting variable for number of times we tried to ping a given server
  $i = 0
  Do{
     #assume a failure
     $pingsuccess = $false 
     $i++ #Add one to the counting variable.....1st try....2nd try....3rd try etc...
     Try{
         #Try to ping
         $currentping = (test-connection $server -count 1 -ErrorAction Stop).responsetime 
         #If success full, set success variable
         $pingsuccess = $true
     }
     #Catch the failure and set the success variable to false
     Catch {
      $pingsuccess = $false 
      }     
  }
  #Try everything between Do and While up to 5 times, or while $pingsuccess is not true
  While($pingsuccess -eq $false -and $i -le 5) 
  #Compare the last ping test with the best known ping test....if there is no known best ping test, assume this one is the best $bestping = $currentping 
  If($pingsuccess -and ($currentping -lt $bestping -or (!($bestping)))){ 
  #If this is the best ping...save it
        $bestserver = $server    #Save the best server
        $bestping = $currentping #Save the best ping results
  }
  write-host "tested: $server at $currentping ms after $i attempts" #write the results of the test for this server
}
write-host "`r`n The server with the best ping is: $bestserver at $bestping ms`r`n" #write the end result
Pause

Linux Shell Script

Pings several voip.ms servers

  #!/bin/sh
  # Ping several servers and display Latency, Jitter and Packet Loss 
  #
  # First, create a text file with all servers you want to ping - one host name per line. 
  # The list of voip.ms servers is available at http://wiki.voip.ms/article/Choosing_Server
  myHF="voip_ping_hosts.txt"
  # Sample file:
  #    toronto.voip.ms
  #    montreal.voip.ms
  #    seattle.voip.ms
  #    chicago.voip.ms
  #    newyork.voip.ms
  #
  echo "============================================"
  printf "%-20s %7s %8s %6s\n" "VoIP Server" "Latency" "Jitter" "Loss"
  echo "============================================"
  cat ${myHF} |\
  while read myLn
  do
     ping -c 3 -i 5 -q $myLn |\
     awk '/^PING / {myH=$2}
          /packet loss/ {myPL=$6}
          /min\/avg\/max/ {
             split($4,myS,"/")
             printf( "%-20s    %3.1f    %1.3f   %4s\n", myH, myS[2], myS[4], myPL)
         }'
  done
  echo "============================================"

Output:

  ============================================
  VoIP Server          Latency   Jitter   Loss
  ============================================
  toronto.voip.ms         68.3    0.439     0%
  montreal.voip.ms        89.6    0.197     0%
  seattle.voip.ms         71.2    0.387     0%
  chicago.voip.ms         71.6    0.084     0%
  newyork.voip.ms         79.1    0.411     0%
  ============================================

Using PingInfoView (Freeware, Windows Only)

PingInfoView is a tool that allows you to ping multiple servers at once which can be quite useful given the extended list of servers provided by Voip.ms. The tool can be found here (no affiliation with the author or voip.ms; direct download link here) and requires no installation, you can execute it directly from the zip file.

Server list (same as the list above, but simplified for easier copy/paste into the tool):

Output:

Latency and its importance

Latency is very important for Voip, this will determine the time that will take for the data package transmission to reach the destination. A high latency will lead to a delay and echoes in the communication.

Latency is measured in milliseconds (ms) For example: a latency of 150ms is barely noticeable, thus acceptable. Higher than that, quality starts to suffer. When it gets higher than 300 ms, it becomes unacceptable.