Software router and methods for looking up routing table and for updating routing entry of the software router

A method for looking up a routing table in a software router which comprises a main memory and a central processing unit (CPU), where the main memory comprises a hash table consisting of one or more buckets (hereinafter, referred to as “buckets A”) wherein each bucket stores destination information to which a unique key is mapped, and the CPU comprises a temporary table to store the destination information present in the hash table, the method comprising:

• determining a location of a bucket (hereinafter, referred to as “bucket B”) in the temporary table by applying a specific key to a designated hash function where the specific key is extracted from a received packet;
• and
• transmitting the received packet to a destination by obtaining destination information from bucket B at the determined location in the temporary table.

A method for updating a routing entry in a software router which comprises a main memory and a central processing unit (CPU), where the main memory comprises a hash table consisting of one or more buckets (hereinafter, referred to as “buckets A”) wherein each bucket stores destination information to which a unique key is mapped, and the CPU comprises a temporary table to store the destination information present in the hash table, the method comprising:

• storing an additional routing entry in bucket A of the hash table, and storing the additional routing entry in a bucket (hereinafter, referred to as a “bucket B”) in the temporary table that is mapped with said bucket A;
• and
• deleting a specific routing entry from bucket A of the hash table and deleting destination information from said bucket B.