Using Multi-Gigabit Switches as a Philosophy of Compromise
What to do when you need speeds greater than 1Gbps, and only the old SCS of category 5E is available and you can’t change it. Where to connect the latest access points with the speed of > 3Gbps - really to the old gigabit network? And what to do if you want to carry out a network to a remote office, where it is impossible to forward an additional twisted pair or fiber?
When Wi-Fi speed exceeds gigabit per second
Usually Wi-Fi was in the role if not catching up, then repeating the development of wired connections. So it was right up to the implementation of the standard 802.11ac Wave2 . New Wi-Fi devices are now able to provide speeds faster than standard Gigabit Ethernet. The result was a very interesting situation. Further development of Wi-Fi up to Wi-Fi 6 only exacerbated the inconsistency of the traditional gigabit network and new wireless technologies.
Table 1 lists the two "shooters" of wired gigabit, which, in principle, served as the reason for the creation of multi-gigabit switches.
Table 1. Wi-Fi standards 802.11ac Wave2 and 802.11ad
|Baud Rate||up to 3.47Gbs (8 bandwidths, 160MHz per band).||up to 6.7Gbps on OFDM (64QAMI)|
In addition to increasing the data transfer speed, the new standards support the MU ‑ MIMO function, with which you can more effectively distribute the available bandwidth between several wireless clients working simultaneously. For example, an access point with a 4x4 antenna configuration will be able to serve two 2x2 clients simultaneously, and not sequentially, as it was before.
As you can see, the existing access level Gigabit Ethernet wired networks are really a bottleneck for faster Wi-Fi connections.
It turns out that while the two devices work with each other within the same access point, they use fairly fast Wi-Fi channels (starting with the standard 802.11ac Wave2).
Figures 1 and 2 show the situation when Wi-Fi clients work within the same access point, however, only one of the exchange participants needs to connect to a remote point connected via a gigabit switch and the transmission speed to this node cannot be higher than 1 gigabit per second.
Figure 1. Communication between two Wi-Fi clients directly through a “fast” access point.
Figure 2. Communication between two Wi-Fi clients through remote points connected via a gigabit switch.
Of course, in the arsenal of local networks there are 10 Gigabit Ethernet, 40 Gigabit Ethernet and even 100 Gigabit Ethernet, but in practice, switching to 10GBE connections would require updating the cable infrastructure from category 5E (or 6) to 6A. But such a massive update of SCS is often not included in the plans of organizations.
As is often the case in IT, I needed a way to "make it impossible." On the one hand, you need to fit into the existing infrastructure in categories 5E and 6, on the other hand, raise the speed to a level comparable to the transmission speed with most modern access points.
As such a “salvation”, the new standards 2.5GBASE-T and 5GBASE-T were made, which describe data transmission at speeds of 2.5 Gbps and 5Gbps, respectively, while avoiding upgrading the cable system.
In combination with the support of Power over Ethernet technology, which allows you to remotely power access points (as well as surveillance cameras, IP phones and other network devices), this is a good solution for combining wired and wireless networks.
At the same time, multigigabit switches themselves can act as not only switches of the access level, but also of the aggregation level.
Wi-Fi 6 Invasion
The Wi-Fi 6 standard, also known as 802.11ax, was announced by the Institute of Electrical and Electronics Engineers (IEEE) and is the next generation of Wi-Fi and the next step in the development of local wireless networks. Based on the capabilities of the 802.11ac standard, Wi-Fi 6 makes it possible to significantly increase data transfer speed and throughput.
Using its access points can support a larger number of clients in high-density environments, and work in standard wireless local area networks becomes easier. In addition, it will provide more predictable performance for today's applications, such as watching 4K and 8K video, high-density and high-resolution collaboration applications, wireless access in offices and the Internet of things (IoT). In the short term, it is Wi-Fi 6 that will determine the future of Wi-Fi networks (see document: IEEE 802.11ax: Sixth Generation Wi-Fi
In some cases, connecting to Wi-Fi 6 access points requires not only a higher speed of the local network (> 1Gbps), but also a higher power supply (PoE ++).
Limitations of multi-gigabit wired connections
Our story will be incomplete if you do not write about some of the nuances that need to be considered when designing.
Unfortunately, even if the transition to the new standard does not require updating the SCS, it is not always possible to get a higher data transfer rate.
With increasing data transfer speed, the requirements for noise immunity and the absence of interference increase. The work of powerful electromagnetic field emitters has a greater effect on multigigabit connections than on standard gigabit.
Another restriction from the category of "de facto" relates to the physical environment of data transmission. At a higher speed, the state of the cable system, the quality of the conductors has a greater role than for connections within the Gigabit Ethernet standard. "Captain Evidence" suggests that if a drop in speed is recorded in this SCS when trying to transfer to 1Gbps, then you should not expect a miracle, trying to achieve a speed of 2.5Gbps.
Another de facto limitation is that not all network adapters for desktops and servers support new standards for wired connections: 2.5GBASE-T and 5GBASE-T. Still, many network cards support only Gigabit Ethernet and 10GBE, which does not allow you to take full advantage of multi-gigabit switches for any situation.
That is, if you want to connect a workstation (desktop PC) or even a server to a 2.5GBASE-T or 5GBASE-T network, you need to be prepared for the fact that you may have to buy the appropriate network adapter.
Such nuances should be immediately taken into account at the initial stage of design, so as not to be surprised at the “wrong” results when introducing new equipment.
Simple and convenient switch for small networks
When designing small entry-level networks, there is a dilemma:
on the one hand, it makes no sense to invest in a universal solution for all occasions because at this stage it is not completely clear: will this infrastructure develop, if so, in which direction;
on the other hand, laying solely within the framework of a narrow decision, without taking into account growth, without the possibility of maneuver - this usually means wasting money, because over time you still have to change something.
Modular solutions help to solve this problem taking into account development.So, at the beginning, one switch is the only one for IT infrastructure, and later, after the aggregation level appears on the network, it becomes one of many access level switches.
On the other hand, if the IT infrastructure does not get development, then its costs should be minimal. Therefore, ease of management and transparency of the settings are welcome.
Switch Zyxel XGS1010-12 is designed to resolve this contradiction. Despite the small number of ports, this is a truly universal solution:
8 ports (1 to 8) Gigabit Ethernet;
2 ports (9 and 10) with 2.5Gbps support;
2 ports (11 and 12) - 10 Gigabit Ethernet SFP +.
For example, you can connect 9 users on workstations and laptops via twisted pair, 1 print server also through twisted pair, additionally hang 2 access points with twisted pair connection to ports 9 and 10 at a speed of 2.5Gbps, and for Uplink Use ports 11 and 12 with fiber optic connection via transceiver.
Figure 3. Zyxel XGS1010-12 12-port unmanaged multigigabit switch with 2 2.5G ports and 2 10G SFP + ports
In Zyxel XGS1010-12 the question of QoS and priorities has been interestingly solved - by setting port characteristics at the hardware level.
From 8 gigabit ports:
ports 7 and 8 have the highest priority;
ports 5 and 6 - medium priority;
the remaining ports 1 through 4 are normal, that is, low priority.
To set the priority of traffic, just connect the patch cord to the desired port. A fairly simple solution that allows you to do without additional settings.
Figure 4. Zyxel XGS1010-12 port mapping.
Universal soldier - Zyxel NebulaFlex XS1930-12HP
A competent approach to network design includes an attempt to lay the foundation for future development. However, to fully know what our future will be is impossible. We may try to forecast based on some industry trends. But what will happen to this organization at least in a year and, especially, with a specific segment of its network - it’s quite difficult to predict.
Therefore, they often lay some reserve, in the expectation that technologies will develop and customers on the network will need support for the maximum available data transfer rates.
In this case, it makes sense to immediately acquire more universal options, such as a multi-gigabit switch Zyxel NebulaFlex XS1930-12HP
The new Zyxel NebulaFlex XS1930-12HP switch supports the latest PoE IEEE 802.3bt (PoE ++) standard, providing port power up to 60 watts for Wi-Fi 6 access points, as well as backward compatibility with existing PoE/PoE + devices. The relatively high 375W PoE power of the XS1930-12HP provides ample headroom for connecting up to 8 Wi-Fi 6 (11ax) access points.
Figure 5. Zyxel NebulaFlex XS1930-12HP 10/12-Port Multi-Gigabit Switch
This “baby” has 10 twisted pair RJ45 ports that support the entire speed range 100M/1G/2.5G/5G/10G. Of which:
8 ports 100M/1G/2.5G/5G/10G and provide power via PoE,
2 ports 100M/1G/2.5G/5G/10G do not support PoE and can be used to connect network equipment, servers, NAS, and so on.
Two more 1G/10G ports (see Figure 6) have an SFP + interface and can be used for Uplink/DownLink, including via fiber-optic connections via the appropriate transceiver.
Of the additional benefits:
Management is possible through the centralized cloud platform Zyxel Nebula.
In this model, color indications of speed on each of the ports are organized quite interestingly. The color indication is shown in table 2.
Table 2. LED color indication of connection speed on Zyxel NebulaFlex XS1930-12HP ports.
|Indicator color||Connection speed|
|Bright Yellow (amber)||100 Mbps|
|Blue (sky-blue)||2.5 Gbps|
|Blue (blue)||10 Gbps|
As a recommendation, it is worth noting that the use of this switch is a good growth solution when network development is planned.
Figure 6. Zyxel NebulaFlex XS1930-12HP port allocation
More use cases: you can hang up 8 access points powered directly through and 2 more powered via PoE injectors, you can connect a server or storage via 10GBE SFP + ports.
Not only for Wi-Fi
Data transmission at a higher speed is required not only for faster access point connections, but also to provide faster Uplink between switches of the access level and the aggregation level on old lines of category 5E.
It is no secret that access level switches are sometimes located at some distance from the central IT infrastructure. For example, if each floor has its own crossover cabinet, then to combine the switches in these cabinets into a single network without the additional cost of laying fiber optic cables or twisted pair cables of a higher category - here multigigabit switches will come in handy.
For the aggregation level of such a heterogeneous network, is good for Zyxel NebulaFlex Pro XS3800-28
Note . Management is possible through the centralized cloud platform Zyxel Nebula.
Figure 7. Zyxel NebulaFlex Pro XS3800-28 10GbE L3 Lite 28-Port Managed Switch
Zyxel NebulaFlex Pro XS3800-28 has:
16 SFP + 10G ports,
8 ports Multi-Gigabit combo (100M/1G/2.5G/5G/10G) RJ ‑ 45/(1G/10G) SFP +,
4 ports 100M/1G/2.5G/5G/10G Ethernet (RJ ‑ 45).
This allows you to realize the aggregation level, which is called, to the maximum, connecting the access level switches both through the usual SFP + interface through the “optics” or twisted pair through the corresponding transceivers, and through the “budget” option, when only the connection through the laid twisted cable is available Category 6 or even 5E pair.
Figure 8. Port allocation Zyxel NebulaFlex Pro XS3800-28 10GbE L3 Lite.
Accordingly, using the 10GBE port aggregation function, you can provide Uplink to the core level of the network.
Note . At the initial stage of development of the network infrastructure, the Zyxel NebulaFlex Pro XS3800-28 can act as the core of the network. A sufficient number of 10GBE ports allows you to use it in this role for a small IT infrastructure.
Progress does not stand still, and nature does not tolerate emptiness.Therefore, any technological niche is filled sooner or later. If some technologies coexist together, then a jerk of one of them will inevitably pull forward the other.
Before deciding on the choice of network equipment, it will not be out of place to look at the manufacturer’s website just in case. Perhaps when you read these lines, a new standard, new equipment and other innovations that need to be taken into account in your work have already come out.
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