Step 1: Build the string request that will be sent to Sell Online
	'         The string is XML formatted and will contain
	'         information such as destination address and
	'         the list of items the consumer ordered
	'
	' TO DO : BUILD YOUR XML STRING HERE
	' Important Note: 
	' --------------
	' This sample is using merchant ID: "CPC_DEMO_HTML"
	' Instead, you should use the merchant ID assigned to you by
	' Canada Post -and- make sure that your profile is configured
	' to return HTML (otherwise, you will receive XML and need an XML parser
	' to understand it).
	Dim xmlRequest
	xmlRequest = " <?xml version=""1.0"" ?> 
					<eparcel>    
					<language> en </language>    
					<ratesAndServicesRequest>
					<merchantCPCID> CPC_DEMO_HTML </merchantCPCID>
					<lineItems>
					<item>
					<quantity> 1 </quantity> 
					<weight> 1.5 </weight>  
					<length> 1 </length>
					<width> 1 </width>  
					<height> 1 </height> 
					 <description> My Sample Item</description> 
					 </item>
					 </lineItems>
					<city>  </city>       
					<provOrState> Wisconsin </provOrState>
					<country>  CANADA </country>
					<postalCode> H3K1E5 </postalCode>
					</ratesAndServicesRequest>
					</eparcel>"

Step 2: The request has to be sent to Sell Online via an HTTP(S) POST request.
Below is the sample request in perl for sending HTTP(S) POST request.

#!/usr/bin/perl

use strict;
use warnings;

use LWP;

my $message = do {
  open my $fh, '<', 'Request.xml' or die "Could not open file: $!";
  local $/;
  <$fh>;
};

my $url = 'https://qa-sellonline.canadapost.ca/sellonline/Rating';

my $ua = LWP::UserAgent->new(ssl_opts => { verify_hostname => 0 });

$ua->proxy(qw/ http proxy:8080 /);
$ua->no_proxy('localhost');

my $req = HTTP::Request->new(POST => $url);
$req->header(Host => 'sellonline.canadapost.ca/sellonline/Rating');
$req->content_type('application/xml; charset=utf-8');
$req->content($message);
$req->authorization_basic('TransportUser', 'TransportUser');

my $response = $ua->request($req);
my $content  = $response->decoded_content;
print $content;

Step 3 : Incorporate the response in your application page. Below is the sample response from sell online :

            <eparcel>
            <ratesAndServicesResponse>
            <statusCode>1</statusCode>
            <statusMessage>OK</statusMessage>
            <requestID>1</requestID>
            <handling>1.0</handling>
            <language>0</language>
            <product id="1020" sequence="1">
            <name>Expedited</name>
            <rate>21.99</rate>
            <shippingDate>2018-09-10</shippingDate>
            <deliveryDate>2018-09-11</deliveryDate>
            <deliveryDayOfWeek>3</deliveryDayOfWeek>
            <nextDayAM>false</nextDayAM>
            <packingID>P_0</packingID>
            </product>
            <product id="1010" sequence="2">
            <name>Regular</name>
            <rate>22.12</rate>
            <shippingDate>2018-09-10</shippingDate>
            <deliveryDate>2018-09-13</deliveryDate>
            <deliveryDayOfWeek>5</deliveryDayOfWeek>
            <nextDayAM>false</nextDayAM>
            <packingID>P_0</packingID>
            </product>
            <packing>
            <packingID>P_0</packingID>
            <box>
            <name>My Sample Item</name>
            <weight>2.0</weight>
            <expediterWeight>1.5</expediterWeight>
            <length>30.0</length>
            <width>20.0</width>
            <height>20.0</height>
            <packedItem>
            <quantity>1</quantity>
            <description>My Sample Item</description>
            </packedItem>
            </box>
            </packing>
            <shippingOptions>
            <insurance>No</insurance>
            <deliveryConfirmation>Yes</deliveryConfirmation>
            <signature>No</signature>
            </shippingOptions>
            <comment/>
            </ratesAndServicesResponse>
            </eparcel>