Posting Specifications and Account Determination 
Posting Specifications and Account Determination
When you define a posting rule, you must specify how each business transaction that is transmitted to you by electronic account statement (for example, bank transfer) is posted in your system.
When you do this you can specify two sets of posting specifications for each posting rule, one for G/L account postings (or bank-related postings) and one for subledger postings.
Depending on whether this posting rules only requires a posting to a G/L account (or bank account) or also requires a subledger posting, you specify posting specifications for either one or both of these postings.
For the "check credit memo" transaction you only require posting specifications for the G/L accounts, since the customer entry is cleared when the check is deposited. However, for a "transfer" transaction, you require posting specifications for both the G/L accounts and the subledger accounts, in order to be able to clear the customer entry.
You enter account symbols rather than the actual account names in posting specifications. You can define these account symbols to meet your requirements.
For account 113100 you could define an account symbol BANK.
For information on account symbols, see
Account Symbols and Account Assignment.Posting specifications consist of a posting key and account symbol (and their attendant specifications) for one or two line items (debit and credit postings). The system uses the account symbol to determine the G/L account to which to make the posting.