An irrevocable Letter of Credit is also an often used payment method. It is often referred to an L/C. Letters of Credit are formal payment methods that offer a lot of protection to the parties.
Simply put, a letter of credit is a letter written by the importer's bank to the exporter. It verifies that the payment will be guaranteed when the bank is presented with the concrete documents (bill of lading, and freight documents). Most letters of credit are "irrevocable" once the importer has had them sent.
Online education has many advantages. The best one is you are able to set up your learning schedule yourself. You are no more at your childhood to spend your full time going to school. You may be looking for a career promotion or job move that requires degree of further education, or you just need to learn something new.
The IP base is for the Standard Multilayer Software Image (SMI) switches, and the IP services image is for the Enhanced Standard Multilayer Software Image (EMI) switches in Cisco IOS Software Release 12.2(25)SEB and later.