Fundamental Limits of Covert Bit Insertion in Packets
Fundamental Limits of Covert Bit Insertion in Packets
复制标题
数据包中隐蔽位插入的基本限制
DOI：
--
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Amir Houmansadr
中科院分区：
文献类型：
--
作者：
Ramin Soltani;D. Goeckel;D. Towsley;Amir Houmansadr
当暴露消息的存在将敏感信息泄露给攻击者时，隐蔽通信是必要的。考虑一个网络链路，其中授权的发送者Jack向授权的接收者Steve发送分组，并且分组在到达Steve之前分别访问Alice、Willie和Bob。隐蔽发送者Alice希望以某种方式改变分组流，以将信息发送到隐蔽接收者Bob，而没有警惕和有能力的对手Willie能够检测到消息的存在。在我们以前的工作中，我们解决了两个技术，这样的隐蔽传输从爱丽丝到鲍勃：数据包插入和数据包定时。在本文中，我们考虑通过在具有可用空间的数据包中插入比特来进行隐蔽通信（例如，尺寸小于最大传输单元）。我们考虑三种情形：1）分组大小是独立且同分布的（i.i.d.）具有概率质量函数（PMF），其支持是一组一比特间隔值; 2）分组大小是I.I. D。其支持是任意的; 3）分组大小可以是相关的。对于第一个和第二个假设，我们表明，爱丽丝可以隐蔽地插入$O（sqrt{n}）$位的信息流的n个数据包，相反，如果她插入$omega（sqrt{n}）$位的信息，威利可以检测到她任意小的错误概率。对于第三个假设，我们证明了Alice可以在n个数据包的序列中秘密插入平均$O（c（n）/sqrt{n}）$位，其中$c（n）$是给定历史的数据包大小的条件pmf的平均数，支持至少为2。
Covert communication is necessary when revealing the mere existence of a message leaks sensitive information to an attacker. Consider a network link where an authorized transmitter Jack sends packets to an authorized receiver Steve, and the packets visit Alice, Willie, and Bob, respectively, before they reach Steve. Covert transmitter Alice wishes to alter the packet stream in some way to send information to covert receiver Bob without watchful and capable adversary Willie being able to detect the presence of the message. In our previous works, we addressed two techniques for such covert transmission from Alice to Bob: packet insertion and packet timing. In this paper, we consider covert communication via bit insertion in packets with available space (e.g., with size less than the maximum transmission unit). We consider three scenarios: 1) packet sizes are independent and identically distributed (i.i.d.) with a probability mass function (pmf) whose support is a set of one bit spaced values; 2) packet sizes are i.i.d. with a pmf whose support is arbitrary; 3) packet sizes may be dependent. For the first and second assumptions, we show that Alice can covertly insert $O(sqrt{n})$ bits of information in a flow of n packets; conversely, if she inserts $omega(sqrt{n})$ bits of information, Willie can detect her with arbitrarily small error probability. For the third assumption, we prove Alice can covertly insert on average $O(c(n)/sqrt{n})$ bits in a sequence of n packets, where $c(n)$ is the average number of conditional pmf of packet sizes given the history, with a support of at least size two.
影响因子：
2.5
作者：
Nazanin Takbiri;Amir Houmansadr;D. Goeckel;H. Pishro-Nik
通讯作者：
Nazanin Takbiri;Amir Houmansadr;D. Goeckel;H. Pishro-Nik
不可见流指纹识别的基本限制
DOI：
10.1109/tifs.2019.2919870
发表时间：
2020
影响因子：
6.8
作者：
Soltani, Ramin;Goeckel, Dennis;Towsley, Don;Houmansadr, Amir
通讯作者：
Houmansadr, Amir