This document describes the Content-Centric Mobile Social Networking (CCMSN) protocol. The protocol has 5 steps: 1) Initialization where node A's interests are obtained, 2) Content transfer where matching contents are scheduled and forwarded to A, 3) Content reception where received contents are stored or replace existing contents based on utility, 4) End transfer when nodes are out of range, and 5) Interest management where interest utilities are updated and new interests are stored or replace existing interests based on utility.

1. Content/Interest
ManagementBlock
Scheduling Block
Link Controller Block
Bluetooth
Application Interface
Tit-for-Tat Trading & Forwarding
Block
Application 1
Content
Storage
Interest
Storage
…
Wi-Fi

2. Description
Binary Data
Content Record
Utility
Interest Record
TTL
Source Id(Def: Unknown)
TTL
Key Words
Utility
Signature + Key
Signed Info
(source Id, description, data)

3. CCMSN Protocol (A, B ):
1. Initialization: Obtain list of Interests from A.
2. Content Transfer: Schedule the Contents that match
the received Interests and negotiate their forwarding
to the node A.
3. Content Reception: For each Content C the node B
receives:
(a) If C is already in B’ store then ignore it.
(b) If B’ store is not full then add C.
(c) If B’ store is full then estimate utility of C and add it on
the behalf of an already stored content with a smaller
utility if found.
4. End Transfer: when out of radio range or all
requested contents transferred.
5. Interest Management: Update the utilities of both
the received Interests and the already stored ones.
Then, for each received Interest I from B:
(a) If I is already in A’s store then aggregates both of them.
(b) If A’ Interests store is not full then add it.
(c) If A’ Interests store is full then add I on the behalf of an
already stored Interest with a smaller utility if found.

4. Interest Storage
UI(s): User
Interests
FI(s):Foreign
Interests
U(I) always =
1
U(I) updated
at each new
meeting
opportunity
U(I): The utility of the interest I.
UI: User Interest.
FI: Foreign Interest.