HK1148138B - A network based on coaxial-cable and communication method thereof - Google Patents

Description

Network based on coaxial cable and communication method thereof

Technical Field

The present invention relates to information networks, and more particularly to transmitting information, such as media information, over communication lines (e.g., coaxial cables) that make up a communication network.

Background

In general, coaxial cables are mostly used in home network technology. Multimedia over coax alliance (MoCA)^TM) The appropriate specifications (MoCA 1.0) are provided on its website mocelliance.org to transmit digital video and entertainment over the existing coaxial cable network in the home, which has been distributed to open members. The present invention is incorporated by reference and in its entirety into the MoCA 1.0 specification.

Coaxial cable based home networking accesses the vast amount of unused bandwidth available on the in-home coaxial cable. Over 70% of homes in the united states have coaxial cables installed in their home network infrastructure. Many homes are arranged with coaxial cables at one or more major entertainment consumption locations, such as the family room, the media room, and the master bedroom, to utilize the network. Home networking technology enables owners to use this architecture as a network system and deliver entertainment and information programs with high QoS (quality of service).

Home networking over coax technology provides high speed (270mbps), high QoS, and inherent security brought by the combination of shielding, wired connections, and packet-level encryption technology. Coaxial cables are designed to transmit high bandwidth video. Today, it is common to deliver millions of dollars of pay-per-view and premium video content securely. A home network based on coaxial cable may also serve as a backbone for a number of wireless access points that are used to extend the coverage of the wireless network throughout the user's residence.

A coaxial cable based home network provides a robust, high throughput, high quality connection to a location in a home where video equipment is located through deployed coaxial cable. Home networks based on coaxial cable provide the main link primarily for digital entertainment, and other wired and wireless networks may also be connected to extend the entertainment experience throughout the home.

Currently, home networks based on coaxial cable work in conjunction with access technologies including, for example, ADSL and VDSL services or Fiber To The Home (FTTH), which typically enter the home via twisted pair or fiber, with operating bands from a few hundred KHz to 8.5MHz (for ADSL) or 12MHz (for VDSL). When the service is to the home via xDSL or FTTH, it can be delivered to the video equipment via home network technology based on coaxial cable and in-home coaxial cable. Wired service functions, such as video, voice and internet access provided by a wired service operator, may be provided to the home via coaxial cable and used to reach various wired service consuming devices in various rooms of the home's residence using the coaxial cable disposed within the home. Generally, home network-like functions based on coaxial cables run in parallel with wired service functions on different frequencies.

It is very desirable to reduce latency and increase throughput by connecting packets in a MoCA home network.

Disclosure of Invention

A system and/or method for reducing latency and/or increasing throughput by concatenating data packets in a MoCA home network, substantially as shown in and/or described in connection with at least one of the figures, as set forth more completely in the claims.

According to an aspect of the present invention, there is provided a coaxial cable-based network, the network comprising:

a plurality of networking nodes (network nodes);

wherein the transmitter of at least one of the networking nodes is configured to transmit a message comprising a connected burst (connected burst), the connected burst comprising:

a preamble;

a first payload; and

a second payload, wherein the first payload and the second payload are separated by a cyclic prefix (cyclic prefix) of a first symbol of the second payload.

Preferably, the networking node comprises a receiver configured to request a message comprising a connection burst.

Preferably, the concatenated burst comprises a third payload, the second and third payloads being separated by a cyclic prefix of a first symbol of the third payload.

Preferably, the concatenated burst includes a fourth payload, the third and fourth payloads separated by a cyclic prefix of a first symbol of the fourth payload.

Preferably, the preamble is transmitted after an inter-frame gap.

Preferably, the last payload in the pulse (burst) is transmitted before the inter-frame gap.

According to yet another aspect of the present invention, there is provided a method of communicating between a plurality of network modules over a coax backbone in a network having the plurality of network modules, the method comprising:

transmitting a connection burst (concatenated burst) message from a first node, wherein the connection burst message comprises:

a preamble;

a first payload frame;

a second payload frame, wherein the first payload frame and the second payload frame are separated by a cyclic prefix (cyclic prefix) of a first symbol of the second payload frame; and

the connection pulse message is received at the second node.

Preferably, the method further comprises requesting a message containing a connect pulse using a networking node configured as a receiver.

Preferably, the method further comprises: a third payload frame is included in the concatenated burst, the second and third payload frames being separated by a cyclic prefix of a first symbol of the third payload frame.

Preferably, the method further comprises: a third payload frame and a fourth payload frame are included in the concatenated burst, the third and fourth payload frames being separated by a cyclic prefix of a first symbol of the fourth payload frame.

Preferably, the method further comprises transmitting the preamble immediately after an inter-frame gap.

Preferably, the method further comprises transmitting the second payload immediately prior to a frame gap.

A more complete understanding of the various advantages, aspects, and novel features of the invention, as well as details of an illustrated embodiment thereof, may be had by reference to the following description and drawings.

Drawings

FIG. 1 is a diagram of a conventional connectionless PHY frame transmission;

FIG. 2 is a diagram of an exemplary set of concatenated PHY frame transmissions in accordance with the present invention;

FIG. 3 is a schematic diagram of a cyclic prefix in accordance with the present invention;

FIG. 4 is a schematic diagram of the performance improvement attributed to connections in accordance with the present invention relative to the non-connection PHY rates;

FIG. 5 is a schematic diagram of an exemplary single-chip or multi-chip module of the present invention in a data processing system.

Fig. 6 is a schematic diagram of an exemplary MoCA network for use with systems and methods according to the present invention.

Detailed Description

Various embodiments to be described hereinafter will reference the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional modifications may be made to the embodiments set forth herein without departing from the scope and spirit of the present invention.

After reading the following description, it will be apparent to one skilled in the art that various features described herein can be implemented in a method, data processing system, or computer program product. Accordingly, these features may be embodied entirely in hardware, entirely in software, or in a combination of hardware and software. Furthermore, the above-described features may also be embodied in the form of a computer program product stored on one or more computer-readable storage media having computer-readable program code segments or instructions embodied in the storage medium. Any suitable computer readable storage medium may be utilized including hard disks, CD-ROMs, optical storage devices, magnetic storage devices, and/or combinations of the foregoing.

In addition, various signals carrying data or events described herein may be transmitted between a source station and a destination station in the form of electromagnetic waves through signal-conducting media such as metal wires, optical fibers, and/or wireless transmission media (e.g., air and/or space).

In a MoCA network environment, traffic transmitted by a node is a mix of multiple video streams destined for multiple target devices, and video and data are transmitted simultaneously. In conventional MoCA systems, each priority stream and each unicast stream (both described in detail below) are typically transmitted separately. Each transmission creates overhead (overhead) which in turn reduces the effective data transmission bandwidth of the network.

The present invention sets forth a system and method for maximizing the available bandwidth of a MoCA device by concatenating data transmission packets destined for different nodes and forming part of a burst, or data transmission packets having different priorities and forming part of a burst. The bursts include additional transmission time overhead, including overhead in the form of frame gaps, which are required between every two bursts, and burst preambles, which are required before the start of each burst. In the MoCA 1.x specification, these pulses are transmitted as a single pulse. Concatenating data transmission packets in multiple bursts can significantly reduce the overhead associated with the frame spacing and burst preamble.

Systems and methods consistent with the present invention may allow more video streams and/or higher definition video streams to be run simultaneously in a home environment. Such systems and methods may also enhance the user experience when the real-time interactive application is running simultaneously with a time-bound service. Examples of such interactive applications that run concurrently with time-limited services include: while watching HD movies on multiple televisions, participate in network games and/or internet surfing.

For reference, the glossary given below provides various abbreviations (abbrevation) and labels used in the present patent application:

ARP Address Resolution Protocol (Address Resolution Protocol)

DAU Data distribution Unit (Data Allocation Unit)

The digital PHY includes a port of the MoCA integrated circuit that is the path for signal transmission to and from the receiver and/or transceiver integrated circuits.

EN MoCA existing node (the term "node" may also be referred to herein as a "module")

IE information element (information element)

IFG frame gap

IDFT Inverse Discrete Fourier Transform (Inverse Discrete Fourier Transform)

MAC medium access control; logic including a MoCA IC to schedule the turning on and off of the required digital PHYs when transmitting and/or receiving signals from the receiver and/or transceiver ICs

MAP Media Access plan (Media access plan)

MPDU MAC protocol data unit

NC MoCA network controller

OFDM Orthogonal Frequency division multiplexing (Orthogonal Frequency division multiplexing)

OFDMA Orthogonal Frequency division multiplexing Allocation (Orthogonal Frequency division multiplexing Allocation)

Physical layer of PHY MoCA network

Quality of Service for PQoS pre-allocation (Provisioned Quality of Service)

RO Reservation Request Opportunity (ReservationRequest Opportunity)

RR Reservation Request message (Reservation Request message)

STB Set up Box (Set Top Box)

It should be noted that in this document, the term "aggregation" refers to the processing performed by an EN when the EN receives a plurality of packets and requests a transmission timing (TxOP) of the packets. An EN may request multiple txops for a frame to transmit a packet that has been aggregated at the EN.

The term "Concatenation" refers to the processing performed by the NC, and may concatenate some packets collected at EN into a single frame. Concatenating two communication bursts into one burst may reduce PHY overhead. Such overhead may be manifested as the network bandwidth it occupies.

In one embodiment of the present invention, such a connection may reduce overhead by one preamble and one frame gap per connection packet, as will be described in detail below with respect to fig. 1 and 2.

In a MoCA network according to the invention there is a trade-off between the data transmission packet transmission delay and the packet aggregation level (i.e. the degree of packet connectivity). Frames comprising data packets may be transmitted in each MAP period (non-concatenated) or may be aggregated and transmitted in every n MAP periods (concatenated). Then, the aggregation level may be increased to reduce the overhead, provided that more transmission delays can be tolerated.

The PHY-level concatenation of the data PHY frame payload according to the present invention will be explained in the following. This application details optional capabilities of PHY-level connections that a node may support. When supported by a node, the node should be able to transmit and receive connected payloads as arranged by the NC.

There are two types of PHY connections according to the present invention: unicast-i.e., from a single transmitting node to a single receiving node; broadcast-i.e., from a single transmitting node to all nodes in the network.

Unicast transmission connections may be applied when the pulses to be connected are destined for the same destination and are not dependent on whether the pulses have the same or different priorities. This approach may concatenate two or more payloads into a single pulse.

A broadcast transmission connection may be applied when the pulses are destined for more than one destination. This method may send the concatenated payload as a broadcast profile (profile). Broadcast transmissions may optimize PHY transmission parameters including, for example, bit loading (bit loading), gain, prefix, etc., for broadcast profiles.

In some embodiments of MoCA networks, for packets with relatively high priority, the EN may request a high priority reservation because there is a possibility: the NC will only provide permission for high priority packets. The NC may concatenate packets from a single EN into a single burst if there is sufficient bandwidth to satisfy all requests, including low priority packets. Such a connection may be applicable to unicast and/or broadcast transmissions.

The following description and the accompanying drawings are directed to connection embodiments in accordance with the present invention. It is noted that the scheduling/scheduling of connection payloads by MAP in accordance with the present invention is an optional feature. Thus, the NC may choose to arrange connections for the payload between the competent nodes, but the NC need not do so.

The structure of the separate, non-concatenated data/control PHY frame payload is as follows.

Fig. 1 shows an exemplary, non-concatenated PHY frame transmission diagram. Transmission 100 includes a preamble 102 followed by a single payload 104 between successive frame gaps 106.

Because concatenated frames according to the present invention do not require a preamble, each concatenated frame can eliminate one frame gap and one preamble. For example, using the system and method according to the invention, the NC may be arranged such that: between two consecutive frame gaps, following a single preamble, up to 4 separate data/control PHY frame payloads are concatenated, each structurally independent. In other embodiments of the invention, more than 4 payloads may be connected.

An example of such a connection transmission is shown in fig. 2, starting with a minimum number of connections of 2 payloads and then up to 4 payloads. Note that the payload of each connection: is an integer number of symbols; and begins with a ciphertext block chaining (ciphertext block chai) of the Advanced Encryption Standard (AES)ning, CBC for short) messages (if privacy is supported); with independent FEC optimization; reset data scrambler (data-scrambler) (using e.g. 23 degree polynomial X²³+X⁵+1 the generated pseudo-random sequence scrambles each byte of the OFDM symbol stuffing frame); resetting constellation binary-scramblers (using the phase of each subcarrier-that is, each subcarrier is modulated by one or more PHY payload bits-may be performed, for example, using generator polynomial X¹⁵The 15 pseudorandom noise (PN-15) sequences defined by + X + 1).

As described above, fig. 2 shows an exemplary PHY-level connection data PHY frame payload transmission diagram. These transmissions include transmissions 200, 201, 203.

Each transmission 200, 201, 203 is shown with a preamble 202 and a plurality of concatenated payloads 204. Each transmission is shown arranged between two frame gaps 206. In addition, an Ncp (cyclic prefix length)210 is included between the last symbol of the first exemplary payload 208 and the first payload of the second exemplary payload 212.

After the first payload of a concatenated packet, the payload of each concatenation should immediately follow the previous payload and start with the cyclic prefix of the first symbol of the payload (as shown by Ncp210 of fig. 2).

Fig. 3 shows a schematic diagram of inserting a cyclic prefix 300. During the transition of an OFDM symbol (which is a structural element of a data packet) from the frequency domain to the time domain, a cyclic prefix is added to the OFDM symbol as part of the OFDM modulation, as described below.

OFDM modulation procedure will be N_SYMGroup N_FFTConversion of frequency domain subcarriers into a set of N_SYMOne OFDM modulation symbol. Each comprising N_FFT+N_CPA time domain sample. The modulation mechanism is functionally equivalent to the reference model described by the following equation. Complex number to be input to OFDM modulator by calculating IDFT outputThe stream is converted into time-domain samples in response to 512 complex blocks X n]＝(I_n+jQ_n) The OFDM input symbol above. For N_FFTFrequency domain symbol of point X [ n ]]The mathematical definition of this operation is, in general, as follows:

and

wherein N is N_FFTN represents the subcarrier index number 512.

The IDFT output 302 is converted to OFDM output symbols 304. To form an OFDM output symbol 304 from the output 302 of the IDFT, the last Ncp samples of the IDFT output 302 are copied and added to form the OFDM output symbol 304. The cyclic prefix length Ncp is unchanged for all PHY payload symbols in a particular PHY frame.

Fig. 4 shows a schematic diagram of the performance improvement due to the connection corresponding to the PHY rate. The X-axis represents PHY rate. The Y-axis represents the time ratio of: the time required for the selected predetermined data stream to be transmitted connectively, the time required for the selected same predetermined data stream to be transmitted non-connectively.

Each set of data points corresponds to a different case, as shown in the figure. The top set of data points shown in the legend corresponds to the broadcast transmission of two high definition video streams of 10Mbit per second. The next set of data points corresponds to a broadcast transmission of two high definition video streams of 20Mbit per second. The next set of data points corresponds to a unicast transmission of 10Mbit of two high definition video streams per second. The next set of data points corresponds to a unicast transmission of two high definition video streams of 20Mbit per second.

Fig. 4 shows a number of points. First, because the values of most data points are less than 1 on the y-axis, the illustrated information demonstrates that the time required to transmit using a connection is less than the time required to transmit using a non-connection.

Second, the trend of the data points down the x-axis illustrates that as the PHY rate increases, the time saved by the connection increases. In this regard, the IFG is constant, at least in part because the PHY rate is getting larger, i.e., the actual data requires less transmit time, which improves the degree of savings in connection related overhead.

In addition to the above, the NC may schedule connection transmissions when the following constraints are satisfied:

all connection payloads are generated using the same transmitting node;

the MoCA headers of all connection payloads have the same DESTINATION NODE identification value DESTINATION _ NODE _ ID, typically between 0-15 or 128-254, inclusive;

the source NODE and all target NODEs inform the connection capability with a NODE _ PROTOCOL _ SUPPORT bit 10;

all connection payloads use the same PHY profile-i.e., the same bit loading, Ncp, transmit power control ("TPC") settings;

all connected multicast payloads have the same priority level;

neither connection payload is a control packet;

if privacy is supported, all connection payloads use the same AES key value;

only the first connection payload may be the remaining data segment (fragment) of the previous transmission; and

only the last concatenated payload may be the first segment of the NC-scheduled fragment.

As described above, the connection embodiment according to the present invention can reduce overhead by the amount determined by one preamble and one IFG per connection payload. The preamble is used for 20-30 microseconds ("uSec") during each communication burst transmission. The IFG used before and/or after the data/control PHY frame communication burst, which is used to transmit MAC frames in the payload, such as application layer data and MoCA network control information, takes about 5 microseconds. The IFG before and/or after the sounding (probe) PHY frame communication burst, which is used to transmit media characteristics such as channel estimation and connection characteristics for the purpose of optimizing PHY layer performance, takes about 24 microseconds. The IFG before and/or after the OFDMA PHY frame communication burst takes about 5 microseconds.

In accordance with unicast transmission of the present invention, the NC is able to concatenate the RRs of all ENs and the RR timing of the RR ("ORR") into a single burst. With respect to the ORR element used by the PQoS set and/or connection, the transmitter should specify a minimum Time To Live (TTL) value for the packets in the set and set a maximum set flag or other suitable mechanism to 1 when the set reaches a maximum set size or a maximum set number of packets. The NC may take these parameters into account in the transmission scheduling/scheduling. In this way, throughput may be increased when managing PQoS.

In some embodiments of the invention, each end of the payload may be provided with shortened FEC and OFDM padding — for example, 0 may be padded in the payload portion of the pulse if needed to equalize the payload portion lengths of the pulses. Such techniques allow packet filtering at the PHY level. Filtering at the PHY level allows the node to determine whether to receive the pulse.

If the NC schedules/schedules the payload of a connection according to the present invention, the NC should follow all the included rules specified below.

These rules include: if a flow with a preferred order, defined by { source, destination, priority }, meets some criteria, the transmitter node may reserve bandwidth for the upcoming packet in advance (in advance for). As described above, this pre-reservation may be implemented by ORR.

The ORR may reserve bandwidth for packets in one or both of the following cases: the data packet with the preferred order is not currently arriving in the send buffer but may arrive before the allowed transmission time of the next MAP cycle; PQoS packets are currently in the transmit buffer but can tolerate some delay before transmission. The criteria for applying ORR on a stream with a preferred order are vendor specific (vendor specific). The bandwidth requested by the ORR is based on traffic forecasts.

Typically, the transmitter does not use the RR to reserve bandwidth for the upcoming data packet. But rather use the RR to reserve bandwidth for packets currently waiting to enter the transmit buffer. In addition, the transmitter sends an ORR element in the reservation request frame only if the RR contains regular RR elements of all waiting priority packets.

If the ORR element having the priority is granted by the NC, the transmitter should form an aggregate packet from the buffered packets of the corresponding stream and transmit the aggregate packet to the receiver within the granted time interval. The transmission time of the aggregate packet should not exceed the allowed time interval. If the actual transmission time of the aggregate packet is shorter than the allowed time interval, the padding bits will fill the aggregate packet so that the allowed time interval is fully utilized. If the transmitter does not send a packet within the allowed time period, a dummy MAC frame with padding bits is sent.

A maximum delay limit is associated with each PQoS flow, and thus a TTL value is associated with each PQoS packet. For PQoS packets that are currently in the transmit buffer but have TTL values less than 2 MAP cycle lengths, the transmitter uses the RR to reserve bandwidth. In addition, the transmitter may use the ORR to reserve bandwidth for PQoS packets. The transmitter does not reserve bandwidth in advance for the upcoming PQoS packet. The bandwidth requested by the PQoS ORR is based on the actual size of all QoS packets waiting.

If the PQoS ORR element is licensed by the NC, the transmitter processes the PQoS ORR element in the same manner as the licensed RR element.

Upon receiving RR and ORR elements from all nodes, the NC grants the requests in the following order:

1. a PQoS RR element;

2. a PQoS ORR element, if the total granted PQoS bandwidth is less than a preset threshold percentage (e.g., 80%) of the data bandwidth of the next MAP cycle; the MAP period data bandwidth is defined as the sum of all data MPDU transmission procedures (including preamble and IFG for each data MPDU transmission);

3. a high priority RR element;

4. medium-priority RR elements;

5. a low priority RR element;

6. a background (background) priority RR element;

7. a PQoS ORR element;

8. a high priority ORR element;

9. a medium priority ORR element;

10. a low priority ORR element;

11. background (background) priority ORR element.

For the same priority packet requests of different nodes, the NC should treat all nodes in a non-preferential manner. The granted transmission time is delivered by the usual DAU.

The DAU corresponding to the opportunistic reservation request element is transparent to the receiving node.

The NC should not violate all inclusive rules specified above when deciding whether to concatenate according to the invention or what payload to concatenate according to the invention. The NC should arrange/schedule the payload of the connection according to the precedence order of the grants.

If the NC chooses to schedule/schedule the payload of a connection, the MAP message should contain a separate DAU for each payload of the connection. The duration that the first payload-connected DAU should grant the request, and the IFG and PHY preamble requested in the corresponding request element.

The DAU of the second connection payload should grant a time slot (timeout) that only corresponds to the duration of the requested payload-i.e. the requested integer number of symbols-should specify an IFG _ TYPE of 0x2 (non-IFG) and cannot contain any IFG or preamble. The DAU of the third or fourth connection payload, if any, should be admitted similarly to the DAU of the second connection payload.

The above specified admission order should be used for all unconnected payloads. Followed by the allowed order of the connection payload.

When admitting a connection payload from any flow, i.e. the same source, DESTINATION NODE identification value DESTINATION _ NODE _ ID in MoCA header and order of preference level, the MAP message of the NC should admit DAU for that flow in the same order as the request elements of the flow received in the reservation request from the transmitting NODE.

FIG. 5 is a schematic diagram of a single-chip or multi-chip module 502, which may be one or more integrated circuits, in an exemplary data processing system 500 in accordance with the present invention. Data processing system 500 includes one or more of the following components: I/O circuitry 504, peripherals 506, processor 508, and memory 510. These components are coupled together by a system bus or other interconnect 512 and are disposed on a circuit board 520 that is included in an end-user system 530. System 500 is configured for use in a cable television tuner in accordance with the present invention. It should be noted that system 500 is merely exemplary and is intended to illustrate the present invention and not to limit the scope of the present invention.

Fig. 6 is a schematic diagram of an exemplary MoCA network for use with systems and methods according to the present invention.

Fig. 6 is a schematic diagram of a home network based on a coaxial cable system constructed and operated in accordance with a preferred embodiment of the present invention. The system of fig. 6 transmits data packets (such as channels 610A and 610B shown in fig. 6, hereinafter collectively referred to as "channel 610") over a network of communication channels in a home 615. The channel may be a wired channel such as a cable (e.g., a coaxial cable). At the end of the channel 610 in the home 615 is installed a set of nodes 620, of which 5 nodes 620A-620E are shown by way of example only. At least a part of the nodes (620A and 620E in the present embodiment, hereinafter collectively referred to as "nodes 620") having a packet aggregation function may form an aggregation frame 630A, 630F by aggregating a plurality of packets 640 accumulated at the nodes. If a node has accumulated at least one packet 640, each node will eventually send a frame containing those packets and perhaps other packets, typically based on permission to either request an admission (as in the illustrated embodiment) or not.

As described in detail below, the system of FIG. 6 is generally configured to perform the following method to transmit a data packet in a network of communication channels interconnecting a set of nodes. The method includes coordinating operation of the set of nodes to access the channel network by granting transmit permission to the respective nodes using the network access coordinator. The method further includes forming an aggregate frame at one or more nodes by aggregating a plurality of packets accumulated at the nodes. The method further comprises transmitting information to the network access coordinator, and accordingly providing the network access coordinator with comparison information of different transmission possibilities for the aggregate frame. If at least one data packet is accumulated at the node, the method includes transmitting the at least one frame in accordance with a grant instruction issued by the network access coordinator to grant transmission to the node. Each frame includes at least one data packet. The coordinator is typically used to determine which portion (if any) of the aggregate packet may be sent.

Typically, each node comprises a modem comprising a model of a CL (convergence) layer, a mac layer and a PHY layer, where the packet aggregation function is performed (at the ECL layer, if the packet is an ethernet packet, abbreviated EPKT).

Each aggregate frame 630A, 630F generally includes at least a portion of the following information: an indicator indicating that the frame is an aggregate frame rather than a single frame and an indicator indicating the size of at least part of the data packets in the frame. This information is typically stored in the header 632 of the aggregate frame. Each packet 640 in each frame has a header with a CRC (cyclic redundancy check) code for the header itself and a CRC code for the packet contents.

The network access coordinator 650, which may itself be a node, coordinates access to the network channel 610 by the plurality of nodes 620 by granting or denying the request to send, or by granting an unsolicited grant to send. At least one node 620 is operable to inform the network access coordinator 650 when it has constructed an aggregate frame 630 comprising at least one aggregated packet 640. The network access coordinator 650 responds by determining which portions of the aggregate packet 640 can be sent.

Typically, as shown in fig. 6, at least one node 620 is configured to send a transmission request, in response to which the network access coordinator 650 optionally grants or refrains from sending. In fig. 6, for example, node 620A requests permission to send three ethernet packets (aggregated in frame 630A) to node 620B, which is located in the bedroom. A grant is requested, albeit in two separate slots (see steps I, II and III (slot III indicating that a separate grant is granted)), where the combined length is sufficient to send three data packets, Epkt1_ A, Epkt2_ A, Epkt3_ a.

Node 620E also requests permission to send three ethernet packets to node 620C located in the kitchen (time slot IV shown). However, the coordinator 650 permits only two of them to be transmitted (time slot V shown in the drawing). Therefore, packet Epkt3 remains at node 620E for a while. As shown, nodes 620B and 620C separate their respective received frames 630A and 630F.

The data packets 640 comprise different classes of data packets and at least one transmitting node 620 is configured to aggregate the data packets stacked at the node as a function of the class (class) to which the data packets belong. For example, in FIG. 6, node 630A is stacked with two class 2 packets, two class 4 packets, and another class 4 packet not grouped with the other two classes. Category 4 is a low priority packet category in the illustrated example. Class 2 packets are characterized, for example, by a common QoS, and/or a common priority, and/or common components in a particular flow, and/or any other packet attribute or set of packet attributes. The rules of the set observed by each node depend on the class. For example, each node 640 is only used to aggregate packets belonging to classes contained in predetermined classes, and to restrict the aggregation of packets belonging to classes other than those predetermined classes.

Each node 640 is configured to aggregate all packets accumulated at the node between each node's transmission of requests. The optional aggregation rule relates to any transmission request or is specific to a transmission request belonging to a particular class of nodes.

In the system of fig. 6, at least one node may periodically send transmission requests.

The system of fig. 6 operates in or in coordination with a home network modem, typically or specifically a coaxial cable based home network, such as a MoCA coax cable based home network as described above. In the MoCA specification, a coordinated home network includes an NC for coordinating access to the medium. Only one node is allowed to transmit at a time, constructing a non-collision network. This facilitates carrying video and voice and data signals over the same network and preserves the video and voice streams and quality of service requirements.

While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. For example, one skilled in the art will appreciate that the steps illustrated in the figures may be performed in other sequences not listed, and that one or more of the steps may be optional. The methods and systems of the embodiments described above may also include other additional elements, steps, executable mass or computer-readable data structures. In this regard, other embodiments disclosed herein can also be partially or fully implemented on computer-readable media, for example, by storing computer-executable instructions or modules or by using computer-readable data structures.

Claims (10)

1. A coaxial cable-based network, comprising:

a plurality of networking nodes;

wherein the transmitter of at least one of the networking nodes is configured to transmit a message comprising a connect pulse comprising:

a preamble;

a first payload immediately following the preamble; and

a second payload, wherein the first payload and the second payload are separated by a cyclic prefix of a first symbol of the second payload,

wherein the first and second payloads are structurally independent.

2. The coaxial cable-based network of claim 1, wherein the networking node comprises a receiver configured to request a message comprising a connect pulse.

3. The coax-based network of claim 1, wherein the connectivity burst comprises a third payload, and wherein the second and third payloads are separated by a cyclic prefix of a first symbol of the third payload.

4. The coax-based network of claim 3, wherein the connection burst comprises a fourth payload, and wherein the third and fourth payloads are separated by a cyclic prefix of a first symbol of the fourth payload.

5. The coax-based network of claim 1, wherein the preamble is transmitted after a frame gap.

6. The coax-based network of claim 1, wherein a last payload of the connection burst is transmitted before a frame gap.

7. A method of communicating among a plurality of network modules over a coaxial cable backbone in a network having the plurality of network modules, the method comprising:

transmitting a connection pulse message from a first node, wherein the connection pulse message comprises: a preamble;

a first payload frame immediately following the preamble;

a second payload frame, wherein the first payload frame and the second payload frame are separated by a cyclic prefix of a first symbol of the second payload frame; and

receiving the connection pulse message at the second node,

wherein the first and second payloads are structurally independent.

8. The method of claim 7, further comprising requesting a message containing a connect pulse using a networking node configured as a receiver.

9. The method of claim 7, further comprising:

a third payload frame is included in the concatenated burst, the second and third payload frames being separated by a cyclic prefix of a first symbol of the third payload frame.

10. The method of claim 9, further comprising:

a third payload frame and a fourth payload frame are included in the concatenated burst, the third and fourth payload frames being separated by a cyclic prefix of a first symbol of the fourth payload frame.