Questions tagged [communication-protocols]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
1
vote
1answer
16 views

Communication Complexity for Product Distributions

In general for the (two-party) set disjointness problem for inputs of length n, we know that the parties need to communicate $\Omega(n)$. Surprisingly, today I discovered (if I understood correctly) ...
0
votes
1answer
16 views

tcp congestion avoidance

I came across this question: ...
0
votes
1answer
73 views

ip/tcp packet decoding without wireshark

How can we manually read and interpret packets properly without using wireshark? Let's say I have this data (IEEE 802.3 link): Now from the Ethernet header I know that the Destination MAC Address ...
1
vote
0answers
21 views

Sending infinite frames in One-Bit Sliding WIndow Protocol?

I am reading Computer Networks by Andrew S. Tanenbaum and I wonder if there is a mistake in the protocol as I can't find any solution for the following scenario. Suppose the transmitter (A) has only ...
1
vote
2answers
83 views

What are the underlying mechanisms allowing us to unsend an email?

I am currently studying Computer Networking, and I was reading about the different types of Application Layer Protocols. In the book I am reading (Computer Networking: A Top-down Approach) it is ...
1
vote
0answers
21 views

Auxiliary random variables in the analysis of the private information of wiretap channels

I am following Section 13.2 of Mark Wilde's book. I reproduce the question here for completeness. Consider a wiretap channel $X\rightarrow Y,Z$ defined by the conditional probabilities $p(y,z|x)$ for ...
-1
votes
0answers
19 views

Wireless communication

Is Wireless Communication a part of Computer Science ? Is wireless communication is part of electrical engineering or computer science ? how it can be similar or how is can be different?
0
votes
0answers
33 views

Stop and Wait protocol in a half duplex scheme

glad i found this site. would appreciate help with this: in picture i uploaded there's a state diagram of a "stop and wait" protocol in a half duplex channel. we assume current status is (10A). ...
0
votes
0answers
75 views

Are acknowledgements used in CSMA/CD?

To provide context, I have read that CSMA/CD does not rely on acknowledgements and relies on collision signals to check for successful or unsuccessful transmissions (from what was explained in the ...
-3
votes
1answer
73 views

What is the name of this experimental OS?

I am trying to find an OS that had a network to verify it's users. It classified itself in classes going from greatest signifigance to least, and the names were galaxy, system, planet, comet etc. I ...
1
vote
1answer
25 views

Guaranteed existence of a blocking set in the accept definition of Stellar

In the SCP, condition 2 of the accept definition allows a node to vote for one statement and later accept a contradictory one. Condition 2 assumes the existence of a v-blocking set which has not only ...
0
votes
0answers
18 views

How do two internet devices agree on a transfer speed

How does a fast device, let's say 1Gbps router, communicate with a 1Mbps device without loosing lots of data? How do the two devices agree on a speed to transfer at?
1
vote
0answers
80 views

Bit stuffing in ethernet

I am naive to computer networks. I studied bit stuffing protocol which helps in identifying the end of the frame. If we assume a two systems which use ethernet protocol at data link layer. How the end ...
1
vote
1answer
81 views

Where were the ideas of vote, accept and commit phases originally introduced?

In the Stellar Consensus Protocol SCP, the voting procedure follows a 3 phase commit i.e. vote, accept and confirm i.e. see section 5. Is this a novel introduction or has this been previously been ...
1
vote
1answer
87 views

Is a “protocol” a set of algorithms and data structures?

I'm not major in science at all and would like to verify whether my understanding is correct or not. I just did some googling about the definition of protocol, such as in this, this one, this one and ...
2
votes
1answer
94 views

Is the capacity achieving input of a discrete memoryless channel unique?

Consider a classical discrete memoryless channel (DMC). Let $p$ be an input probability distribution and $Q$ be the channel's transition matrix. $q = Qp$ is a valid output probability distribution. ...
0
votes
0answers
16 views

Go Back N question(netwrok)

Hello I am trying to understand the GBN protocol and I encountered the following question during my homework. Assume that we have GBN protocol with a window size of 20. The sender sends 15 packets ...
1
vote
1answer
115 views

Basic Question in networking - why max data size of ip datagram 65535 BYTES and not 65535 bits?

I recently started computer networks with some understanding of algorithms and discrete mathematics. I am completely new. Kindly elaborate following - data size of ip datagram = 16bits. So with this $...
1
vote
1answer
37 views

Reaching Shannon capacity of a channel

Suppose I have the following from alphabet $\mathcal{X} = \{0 ,1\}$ to $\mathcal{Y} = \{0 ,1\}$. The channel simply does \begin{align} 0 \rightarrow 0&\quad \text{with probability 1} \\ 1 \...
1
vote
1answer
120 views

Finding maximal and average number of time slots in an Adaptive tree walk protocol

Tried to research here and on other sites with no luck regarding finding the maximal and average number of time slots in an Adaptive tree walk protocol. i'll explain what i mean here: In a simple(...
0
votes
1answer
20 views

Can a transcript change dependent random variables into independent variables?

Let's say $X, Y$ are dependent random variables. Can I find an example such that for a transcript $t$ conditioned on a communication protocol $\Pi=t$, the variables become independent?
2
votes
1answer
45 views

Looking for two-way communication/consensus/contract algorithm for use in marriage proposal

I am looking for some sort of communication or consensus algorithm with the following properties: Can be used with just two parties (and ideally doesn't collapse to a trivial case with two parties) ...
0
votes
0answers
96 views

utilization of bitmap protocol

I am curious about utilization calculation in the bitmap protocol. especially if there's a difference between if only station 0 wants to broadcast(and the others doesn't) or only some other station ...
0
votes
0answers
25 views

Affects of altering a line in “stop and wait” protocol(no noises)

what will happen if we change "to_physical_layer(&s)" to "to_physical_layer(&r)" in the following code(marked in the code where)? does it make the protocol fail? if so, show a scenario it ...
1
vote
1answer
97 views

How is the literal meaning of “rendezvous” related to its usage in distributed computing?

I am trying to figure out the difference between RPC and Rendezvous. Is it correct that they differ only on their implementation on server side: RPC will involve creating a new process/thread to ...
1
vote
1answer
101 views

Complexity of sending an $n$-bit string

Consider a $2$-party communication model in which $A$ wish to send to $B$ an $n$-bit string. It is very easy to prove that any deterministic protocol for this problem requires $\Omega(n)$ bits to be ...
1
vote
1answer
70 views

Randomized communication complexity of indexing

The function $\mathrm{INDEX}:\{0,1\}^n\times\{1,\dots,n\}\to \{0,1\}$ is defined as $$\mathrm{INDEX}(x,i)=x_i,$$ where $x=x_1\dots x_n$. I am looking for the randomized communication complexity of $\...
0
votes
2answers
58 views

How to decide which bytes will form a packet ?(computer networks)

In wireless communication , I understand what it means to transmit a "bit" but I wanted to understand what exactly does it mean by a packet . *******POST EDIT/RECEIVING INITIAL ANSWERS******* I got ...
3
votes
1answer
88 views

Private IP and public IP

What we see on our devices is essentially the private IP given to us by the ISP; thereby, whenever we access the internet, this private IP is first converted to public IP (by ISP through NAT), ...
0
votes
1answer
55 views

The role of the root switch after Spanning Tree Protocol has established a tree network in a LAN?

In Spanning Tree Protocol, a root switch is selected at first, and then somehow, the shortest path from each other switch to the root is obtained. Thus we established a tree network. My questions ...
1
vote
0answers
21 views

Why Not To Take B8ZS with encoding 7 digit?

I have a simple question. In signal encoding we have B8ZS (Bipolar with 8 zeros substitutions) technique which encodes every 8 sequencial 0 bits with 000+-0-+ or 000-+0-+ depends on previous voltage ...
-1
votes
2answers
30 views

When packets are not full?

When in computer networks it happens that the packets are not full? I have heard that sometimes in UDP that happens, if that’s the case, why not all the space is not used?
0
votes
1answer
21 views

Is it possible to give a guarantee about the accuracy of the local time?

Assuming there is no attack/bug and I use NTP: Are there any formal guarantees about the accuracy of the local time? Can there be any over the network? Even if the communication is going directly ...
3
votes
2answers
129 views

Finding the total capacity of two communication channels

I have the transition matrices of two communication channels. I am able to find the capacity of each by performing an optimization calculation, however I need the total capacity of the two channels. ...
1
vote
1answer
31 views

Is there an existing protocol where a sender does not know who he is sending data to?

I was thinking about how the BitTorrent protocol automatically gives every peer a list of IPs of every other user who is currently seeding / leeching off the torrent in question. Is there an existing ...
5
votes
1answer
181 views

Could a standardized ternary system be more efficient than the binary system? [duplicate]

Could a standardized ternary (base-3) system be more efficient than the binary (base-2) system? Binary is efficient for processing using logic gates, but can be bulky when using for file storage or ...
0
votes
1answer
88 views

Chord protocol - How should I go about mapping nodes to placeholders on the ring?

In the real world, how is a node mapped to the position on the ring, Each nodes's IP address is hashed using SHA-1 hashing algorithm which will produce this hash - 73.128.154.69 hashed into ...
0
votes
2answers
654 views

Why is RTS/CTS optional?

I was reading in Wikipedia about it and one of the main things that were pointed out was that it is only an optional mechanism. This bugs me more than it should as I cannot find any information that I ...
4
votes
1answer
43 views

Compute the union of two sets between two endpoints minimizing communication complexity

I have two endpoints, $a$ and $b$, that can communicate through a channel. $a$ is storing a set of fixed-length strings $A = \{a_1, \ldots, a_{N_A}\}$, and $b$ is storing another set of fixed-length ...
0
votes
0answers
126 views

Probability in Dynamic frame aloha

If I've RFID Collision Arbitration System that is based on multi-frame dynamic frame ALOHA. How can compute the probability of the average tag resolution $L_n$? ,$P_s$ is probability for packet ...
1
vote
1answer
73 views

Is data received after transmission immediately stored and can that be recovered?

When I send a message from one device to another, during the process during which the other device is receiving the data, is that data stored temporarily on some place on the device or is it ...
2
votes
1answer
84 views

IP Fragmentation

I have an IPv4 packet, 3523 byte of information Data a MTU (maximum transmission unit) of 516 (496 byte + 20 byte IP header), also an TCP header with 20 byte. How does this result is created from the ...
7
votes
1answer
23k views

TCP Connection Termination - FIN, FIN ACK, ACK

I've been reading that to terminate a TCP connection 3 handshakes are required: FIN, FIN ACK, and ACK. However, when closing a connection, Wireshark displays FIN ACK, FIN ACK, ACK; it never displays ...
1
vote
1answer
409 views

Serial communication and parity bit

I was revising Computer Science and I got these two doubts to which I've found contradictory answers on Google: In a serial communication which bit is sent first? When using a parity bit with ASCII ...
1
vote
1answer
469 views

Data link layer Sliding Window utilization formula query

In the data link layer, the Sliding Window is used for flow control. There are two link utilization formula that can be use. They are : U = 1, for N > 2a + 1 OR U = N/(1+2a), for N < 2a + 1 In ...
2
votes
1answer
119 views

Classification of technologies used for communication in distributed systems

I am currently writing a State of Art about technologies used for distributed communication (like CORBA for example). I want to structure the document in way that I don't leave any subset of this ...
2
votes
0answers
51 views

Authority section in DNS packet always contains NS records?

I'm new to DNS and I'm trying to understand the DNS packet format. From what I understand, the authority section of a DNS packet gives information about servers that are authoritative for the domain ...
3
votes
1answer
479 views

The throughput of the ALOHA protocol if the Binomial distribution was used

In all the examples of ALOHA I've seen, the Poisson distribution is used. Theoretically, how could the throughput be calculated if a Binomial distribution was used instead? For example, in the case ...
5
votes
0answers
81 views

How to ensure connectedness in a masterless gossip protocol?

This is a theoretical question about how gossip protocols work; I am not asking about any specific implementation or piece of software. I've read the wikipedia page https://en.wikipedia.org/wiki/...
4
votes
1answer
38 views

What is a “name/variable of base type” in applied $\pi$-calculus?

I'm studying the articleVerifying privacy-type properties of electronic voting protocols which uses Applied $\pi$-calculus to formalize voting protocols and verifies some privacy-related properties. ...