Differences between QSFP28 PSM4, QSFP28 SR4 and QSFP28 LR4

The appearance of the QSFP28 optical transceiver is the same as that of the 40G QSFP + optical transceiver. The difference is that QSFP28 optical transceiver can transmit optical signals up to 100G. Therefore, QSFP28 optical transceiver has become the mainstream 100G optical transceiver and the preferred solution for network upgrade of 100G. This article describes the differences between the QSFP28 PSM4 optical transceiver, the QSFP28 SR4 optical transceiver, and the QSFP28 LR4 optical transceiver.

The Definition of Different Types of QSFP28 Optical Transceiver:

QSFP28 PSM4 optical transceiver is a high-speed, low-power product with a hot-swappable QSFP form factor with built-in digital diagnostics and eight optical fibers, each with a data rate of 25Gbps.

QSFP28 SR4 optical transceiver is a parallel 100G optical transceiver with the advantages of high port density and low cost. If you need a short distance transmission of optical transceivers for 100G network upgrade, you can choose QSFP28 SR4 optical transceiver.

QSFP28 LR4 optical transceiver, an optical transceiver with transmission distances up to 2km, provide an ideal solution for the ever-increasing transmission distance requirements of very large data centers and will lead the use of single-mode optical fibers in the data center.

QSFP28 Optical transceiver Differences:

1. Transmission Methods

As we all know, QSFP28 optical transceiver usually has four transmission channels, and each channel data rate is 25Gbp. This transmission is very similar with 40G QSFP + optical transceiver transmission. 100G QSFP28 SR4 and 100G QSFP28 PSM4 optical transceivers are 12-way MTP interface, while the realization of the 8-way fiber 100G transmission is bidirectional. But the 100G QSFP28 LR4 optical transceivers cannot do this, QSFP28 LR4 optical transceiver is transmitted at the same time in two uses of LC duplex fiber in one direction for 100G transmission.

2. Transmission Media and Transmission Distance

QSFP28 PSM4 optical transceiver, QSFP28 SR4 optical transceiver and QSFP28 LR4 optical transceiver transmission distance are also different. QSFP28 SR4 optical transceiver operates at 850nm and is used with OM3 or OM4 multimode fibers for transmission distances of up to 70m with OM3 fibers and up to 100m with OM4 fibers. QSFP28 LR4 optical transceiver is usually used with single-mode fiber, which operates at 1310 nm and has a maximum transmission distance of up to 2km. QSFP28 PSM4 optical transceiver, is generally used with a 12-way MTP interface and single-mode optical fiber with a transmission distance of up to 500m.

3. The Wiring Structure Is Different

Optical transceiver transmission in the optical fiber routing has a very important role. Because the QSFP28 SR4 optical transceiver and the QSFP28 LR4 optical transceiver are used for short-distance transmission and long-distance transmission respectively, their wiring structures are different. The former requires multi-fiber cabling based on a 12-way MMF MTP interface, while the latter requires only a traditional two-fiber SMF cabling. In this case, the conversion between multimode fiber and single-mode fiber is very complicated because they use a completely different wiring structure.

Although QSFP28 PSM4 optical transceiver operates in single-mode fiber, its wiring structure is the same as that of the QSFP28 SR4 optical transceiver. Using the QSFP28 PSM4 optical transceiver saves conversion costs between multimode and single-mode without changing existing cabling structures.

4. Different Working Principle

(1) How QSFP28 PSM4 optical transceiver works:

The working principle of the QSFP28 PSM4 optical transceiver is almost the same as that of the QSFP28 SR4 optical transceiver. The difference is that the QSFP28 PSM4 optical transceiver operates on single-mode fiber while the QSFP28 SR4 optical transceiver operates on OM4 multimode fiber.

(2) How QSFP28 SR4 optical transceiver works:

QSFP28 SR4 optical transceiver transmits signals at the transmitting end; the electrical signals are converted into optical signals by the laser array and then transmitted in parallel on the ribbon multimode fiber. Upon reaching the receiving termination, the photo detector array converts the parallel optical signals into parallel electrical signals.

(3)How QSFP28 LR4 optical transceiver works:

QSFP28 LR4 optical transceivers are typically used with LC single-mode fiber optic cables to convert 4×25Gbps electrical signals into 4 LAN WDM optical signals and then multiplexed into a single channel for 100G optical transmission. At the receiving end, the module demultiplexes the 100G optical inputs into 4 LAN WDM optical signals, and then converts them into 4 channels of electrical signal output. 

An Introduction to 100G QSFP28 Optical Module and Its Advantages

After the optical module data rate, the development of optical module form factor, the market there are a variety of optical modules and a variety of packages, then QSFP28 optical module now appears, it has some advantages that can help become the mainstream of 100G optical networks. Below, we will introduce to everyone what is QSFP28 optical module and what are the advantages of QSFP28 optical module.

What Is QSFP28 Optical Module?

First, let's look first: What is QSFP28 optical module. Generally speaking, the optical module form factor refers to the optical module shape, with the progress of science and technology, optical module form factor is a step by step evolution, the volume is gradually smaller, of course, not only the appearance of the change in the rate, power consumption, distance , costs, etc. are also constantly moving forward.

Currently 100G optical modules have several main form factors, including: QSFP28 optical module, CFP optical module, CFP2 optical module, CFP4 optical module, these kinds of encapsulated optical modules all belong to 100G, of which the QSFP28 optical module is a mainstream 100G optical module on the current market.

The post will compare 100G QSFP28 optical module and other 100G optical modules in terms of port density, power consumption, and cost respectively.

What Are the Advantages of QSFP28 Optical Module?

1. Port Density

The first generation of 100G optical modules was a very large CFP optical module, and then CFP2 and CFP4 optical modules were launched, among which CFP4 optical module was the latest generation of 100G optical modules and had a width of only 1/4 of the CFP optical modules. However, the form factor of 100G QSFP28 optical module is smaller than the CFP4 optical module, which means the 100G QSFP28 optical module has a higher port density on the switch.

2. Power Consumption

The power consumption of 100G QSFP28 optical module is usually lower than 3.5W while that of other 100G optical modules is usually between 6W and 24W. From this, 100G QSFP28 optical modules have much lower power consumption than other 100G optical modules.

3. Cost

Now the data center is mainly 10G network architecture, in which the interconnection solution is mainly 10GBASE-SR optical module and duplex LC multimode fiber jumper. If the existing 10G network architecture can be directly upgraded to 40 / 100G networks, it will save a lot of time and cost.

Although 100G QSFP28 optical modules have many advantages, it is only one of many solutions for 100G network. For data centers and server rooms, suit is best. Therefore, other 100G optical modules also have a place in the 100G network. Gigalight thinks that 100G QSFP28 optical module series, like 100G QSFP28 SR4, 100G QSFP28 LR4, 100G QSFP28 CWDM4 and 100G QSFP28 PSM4, have brought a new solution for 100G applications that will promote the faster development of 100G.

QSFP-DD (Double Density QSFP): Something You Want to Know

With the rapid growth of data center and 5G development, density, power limits in servers, switches, and other network equipment are being pushed by rising demand and data volume. Data center is required to support faster processing, more bandwidth, and increased density without sacrificing reliability. In this situation, QSFP-DD came out, which is a new module and cage/connector system similar to current QSFP, but with an additional row of contacts providing for an eight lane electrical interface. In this article, we will introduce you something about QSFP-DD that you may be interested in.

1. What Is QSFP-DD?

QSFP-DD stands for Quad Small Form Factor Pluggable Double Density. What Double Density means? The “double density” means the doubling of the number of high-speed electrical interfaces that the module supports compared with a standard QSFP28 module. QSFP-DD is a “double-density” module and cage/connector system which is similar to the current QSFP system. But QSFP-DD has an additional row of contacts providing for an eight-lane electrical interface. The new optical module will be able to operate 25 Gb/s NRZ modulation or 50 Gb/s PAM4 modulation over 16 pairs of twinaxial conductors or optical fibers to support 200 Gb/s or 400 Gb/s aggregate bandwidth.

2. An Introduction on QSFP-DD MSA Group

QSFP-DD Specification for QSFP Double Density 8X Pluggable Transceiver is currently under development by the QSFP-DD MSA Group. The group includes 13 members which are all the leading vendors in the optical communication industry, like Cisco, Brocade and Finisar, aiming to create a upgraded version of QSFP transceiver, which is called QSFP-DD and is able to support 200G/400G Ethernet.
QSFP-DD MSA Group participants have developed an improved management interface. The MSA project may split into separate management interface and form-factor documents. There is a possibility that the OSFP MSA Group, the uQSFP MSA Group, and the Consortium for On-Board Optics (COBO) will adopt the improved QSFP-DD management interface.

3. QSFP-DD vs. QSFP28

QSFP28, with increased data rates ranging up to 28 Gbps on each of four lanes, supports next-generation 100 Gbps Ethernet and 100 Gbps InfiniBand. Now it is quite popular in datacenter computing, switches, routers, and storage. With enhanced Data Rate applications, the QSFP28 interconnect transmits up to 25 Gbps per-serial lane data rates with excellent signal integrity, EMI protection, and thermal cooling.
The QSFP-DD is similar to the current QSFP, but there are still some differences. If modulated by NEZ, each lane of the QSFP-DD can support data rate up to 25G, thus, it can support a total data rate of 200G. If modulated by PAM4, QSFP-DD transceiver can support data rate up to 400G with each lane supporting data rate of 50G. The MSA group also announced that the QSFP-DD can enable up to 14.4Tbps aggregate bandwidth in a single switch slot, which can definitely satisfy the increasing need for higher bandwidth.

4. 200G QSFP-DD

To achieve 400 Gbps, the interconnect industry is developing next-generation Quad Small Form Factor Pluggable Double Density (QSFP-DD) modules. And Gigalight also took the opportunity to release out the new 200G QSFP-DD in this summer. The 200G QSFP-DD integrates eight data lanes in each direction with 8x25.78125Gbps bandwidth. Each lane can operate at 25.78125Gbps up to 70m by using OM3 fiber or 100 m using OM4 fiber. The module is designed to operate over multimode fiber systems using a nominal wavelength of 850nm. It is a high performance module for short-range multi-lane data communication and interconnection applications. It is four-Channel, pluggable, parallel, fiber-optic QSFP+ SR4 for 100 or 40 Gigabit Ethernet, Infiniband FDR/EDR and applications. This transceiver is a high performance module for short-range multi-lane data communication and interconnects applications.

Conclusion

The QSFP-DD optical transceiver is also forward/backward compatible with QSFP, QSFP28 optical transceiver, AOC/DAC and so on. We believe that the rapid development of QSFP-DD will greatly benefit on the whole optical interconnect and communication industry. Let’s wait and see what will happen in the future.

CWDM and DWDM Comparison: What’s the Difference?

DWDM (Dense Wavelength Division Multiplexing) is undoubtedly the popular technology in today's optical fiber applications. However, because of its expensive price, many operators without enough money are quite hesitated to use it. Can we use wavelength division multiplexing at a lower cost? Faced with this demand, CWDM (Coarse Wavelength Division Multiplexing) came into being. And in the post, we will take an introduction on the main difference between CWDM and DWDM and which one is your better choice.

CWDM, as the name suggests, is a DWDM close relative. When comparing CWDM vs. DWDM, their differences are mainly two points as follows:
1. CWDM carrier channel spacing is wide, so the same fiber can only reuse 5 to 6 or so wavelength. This is why we call “Dense” and “Coarse”.
2. CWDM modulates laser by using non-cooling laser, but DWDM is used to cooling laser. The cooled laser is thermally tuned and the non-cooled laser is electronically tuned. Since the temperature distribution is very uneven in a wide wavelength range, the temperature tuning is difficult and costly to achieve. CWDM avoids this difficulty, therefore the cost is significantly reduced, the entire cost of CWDM system is only 30% of DWDM.
CWDM provides very high access bandwidth for low cost, and is suitable for popular network structures such as point-to-point, Ethernet, SONET ring, especially for short distance, high bandwidth, and point-intensive communication applications. Building communication between buildings or buildings. In particular, it is worth mentioning that CWDM and PON (passive optical network) with the use. PON is an inexpensive, point-to-multipoint optical fiber communication method. By combining with CWDM, each individual wavelength channel can be used as the virtual optical link of PON to realize the broadband data transmission between the central node and multiple distributed nodes.
At present, several companies are introducing CWDM-related products. Here we mainly introduce CWDM Mux/Demux and DWDM Mux/Demux.
(1). CWDM Mux/Demux Module:
CWDM Mux and CWDM Demux are designed to multiplex multiple CWDM channels into one or two fibers. The core of CWDM Module application is the passive MUX DEMUX unit. The common configuration is 1×4, 1×8, 1×16 channels. Available in 19″ Rack Mount or LGX module package, optional wide band port is available to multiplex with CWDM Channels wavelength.
(2). DWDM Mux/Demux Module:
DWDM Mux and DWDM DeMux are designed to multiplex multiple DWDM channels into one or two fibers. The common configuration is 4, 8, 16 and 40 channels. These modules passively multiplex the optical signal outputs from 4 or more electronic devices, send them over a single optical fiber and then de-multiplex the signals into separate, distinct signals for input into electronic devices at the other end of the fiber optic link.
However, CWDM is the product of cost and performance compromise; inevitably there are some limitations on performance. Industry experts pointed out that CWDM currently exist below the following four points: First, CWDM in a single fiber to support the number of multiplex wavelengths less, resulting in higher cost of expansion in the future; second, multiplexers, multiplexers, etc. The cost of the equipment should be further reduced, these devices can not only DWDM corresponding equipment, a simple modification; Third, CWDM does not apply to metropolitan area networks, metro nodes between the shorter distance, operators in the CWDM equipment expansion on the money can Used to lay more fiber optic cable, get better results; Fourth, CWDM has not yet formed a standard.
From the CWDM and DWDM comparison above, we can know both the benefits and drawbacks of CWDM and DWDM. If the transmission distance is short and cost is low, then CWDM may be your first choice. On the contrary, you can consider DWDM. For more information about CWDM and DWDM, you can visit: Gigalight.

Major Trends for 100G Ethernet Market

The Ethernet market has grown dramatically over the past few years. Speeding up transmission and expanding the capacity of the data center will help drive this trend. According to IHSInfonetics, 100 Gigabit Ethernet (100G) per second will account for more than 50% of the data center fiber optic transceivers market by 2019. Since 2014, the industry's revenue has increased by 21% to $ 1.4 billion. As the 100G chip is put into production, and 100G Ethernet market speculation is accelerating. But all this is just speculation; perhaps 100G Ethernet transceiver market will have a revolutionary progress?

1. Data Center Architecture and Traffic Changes

At present, the fiber industry's transmission technology reaches gigabits per second (10G) and 40 gigabits per second (40G), which has been around for a long time. These techniques are effective and most people have no objection to this. For most users, the 40G transmission speed is more than enough. The problem of data transmission in the data center becomes apparent. Internet content providers and enterprises in the cloud data on the scale and traffic will continue to grow.

Cisco Systems predicts that Internet data (IP) traffic in the global data center will grow at an annual rate of 31 percent over the next five years. The way people use the Internet changes to make this growth. Cloud computing data volume is growing, the global mobile device access to video social media content data more and more.

Data center construction is increasing, which requires a better data management solution. The influx of traffic has led to changes in the way in which the three-tier network and other changing information flows through the data center movement (ie, a combination of user interfaces, data processors, and database management systems). Newer technologies allow parallel processing and can transfer more data. The Internet is becoming more and more complexed, and websites need more interconnection. The architecture of the data center is changing, focusing more on the integration nodes and increasing the bandwidth. Obviously, 100G will become the new standard for higher bandwidth and smarter data center architecture.

2. 10G Cannot Meet the Growing Needs of the Enterprise Network

Some large data centers have been switched. The Howard Hughes Medical Institute has recently switched to 100G technologies, delivered via the Brocade MLXE router. The data center includes 56 11G ports, all equipped with its efficiency to achieve the highest priority of the switch. Traditionally, the data center will rely on 10G multiple bundles of transmission, requiring link aggregation, and resulting in suboptimal and inefficient load balancing.

This is the 100G useless. It releases space, minimizes data aggregation, and significantly improves overall efficiency. As the size of the enterprise grows and the demand for data becomes more complex, the 100G will provide them with the urgency of bandwidth and efficiency. Companies with four or five 10G ports have witnessed their database growth and may find switching to more affordable and scalable 100G ports. Of course, this is driven by the cost and the resources of the enterprise.

3. The Continuous Development of CMOS Technology Will Make 100 G Become Mainstreams

With the evolution of 10G technology, 100G technology into the mainstream before it takes some time to develop transceiver technology, when it began to use, the cost is expensive, requires a lot of power. With the passage of time, advances in chip technology have reduced more costs and the emergence of various energy-saving technologies. This is exactly 100G technology in the market to win the reasons, and the use of CMOS technology to become the industry standard. Because the use of CMOS architecture will make it faster, while using less power.

Once the technology is mature, the 100G system architecture can save more power and provide up to 10 times the speed. At present, Cisco and Brocade Communications Systems sell 100G switches and routers at the enterprise level. But the average cost per port of its switch is $ 2,500, which means that companies using 100G network to pay a high price. However, with the development of CMOS technology, the creation of these systems will become easier and more affordable. Many optical communication manufacturers, like Gigalight, launched various kinds of 100G products, such as 100G QSFP28. These systems will reduce costs, reduce data center size and power requirements, and make 100G applications mainstream.

Ethernet vs Internet: What's the Difference?

As we all know, both internet and Ethernet belong to types of networks that are used to connect computers.  However, to some degree, they differ in many aspects. Then if we want to compare Ethernet vs Internet, what are their differences? In this article, we will discuss it in detail.

  Internet is one of networks, composed of millions of ones from the local to the private, the governmental, the academic, and the corporate in the globe and connected by a series of techs, such as electronic tech, wireless tech, optical fiber network tech and so on. While  the Ethernet is the base LAN  standard created by Xerox, and jointly developed into the one by Xerox, Intel and DEC. It adopts the CSMA/CD access control method and is conformed to IEEE802.3.

  In fact, the difference between them has been shown from the introduction, but the difference between them i s far more than this. More differences are reflected in these respects.

What Is the Difference Between Internet and Ethernet?

  For one thing, in terms of connection range, compared with Ethernet, the connection range of internet is far wider than that of it. Ethernet belongs to one of Local Area Network(LAN), mainly responsible for the interconnections of computers in local areas. Generally speaking, the interconnections of computers in local areas usually happen in the same building or in the neighborhood. However, with the developments of Ethernet cables, the connection range of the Ethernet can be expanded to ten kilometers. Even so, in some sense, it's impractical to achieve the long-distance interconnection between computers. While internet belongs to one of Wide Area Network (WAN), able to connect networks all over the world.  The private, the governmental, the academic, and the corporate network in the globe are connected with each other to share massive information, resources and services.

  For another thing, they distinguish in the aspects of transmission media and tech. The Ethernet applies twisted pair and fiber as the transmission media and adopts CSMA/CD(Carrier Sense Multiple Access with Collision Detection )method. While internet doesn’t use some specific tech or transmission media, it contains all transmission medias  and techs.

  In addition, they also differ in respect of the network administration. Ethernet can have one or more administrators; while parts of internet are administrated by administrators, but there is no administrators  to control the whole internet.

  Finally, there are differences in security of network. By comparison, the Ethernet is with higher security than internet. External people have no access to it; while internet is accessible to all of people.

Article souce: www.gigalight.com

3 Types of SFP Transceivers That You Want to Know

There are many types of SFP transceivers in the current market. Gigalight supply various types of SFP module 100% compatible with Cisco SFP, HP SFP , Juniper SFP, Netgear SFP, DELL SFP CWDM SFP, DWDM SFP, BIDI SFP, 10G SFP and so on. For many SFP transceiver types, I will introduce three main types of SFP transceiver modules in detail.

1.       CWDM SFP Transceiver :

CWDM SFP (Small Form Factor Pluggable) transceiver is actually an optical transceiver compact used in communications optics both for applications in telecommunication and communication of data on the wavelength. CWDM SFP are widely used to link the ports of the network of fiber optics, typical CWDM SFP as Cisco could support both Gigabit Ethernet and Fiber Channel . CWDM SFP modules take advantage of the SFP interface for connecting the computer and use interface connector fiber PC LC double for the connection of the network optics. Gigalight CWDM SFP transceivers can be found with a number of different types of transmitter and receiver, allowing users to decide on the appropriate transceiver for each link to provide the required optical range over the available optical fiber.

2.       DWDM SFP Transceiver:

Dense wavelength multiplexing transceivers (DWDM Division) offer DWDM transport with far lower power and the cost of a standard SFP pluggable package. DWDM SFP is available in all wavelengths of 100 GHz C / L bandwidth of ITU DWDM network. As multifrequency user interfaces that support all protocols from 100 Mbps to 4.25 Gbps. The modules meet the requirements of the Gigabit Ethernet IEEE802.3 standard ANSI specifications and channel of fiber, they are suitable for interconnections in Gigabit Ethernet environments and channel of fiber. The DWDM SFP was created to accept DWDM SONET / SDH (with or without FEC) for 200 miles links and Ethernet / fiber protocol channel of traffic to the links 80 miles.

3.       10G SFP Transceiver :

The 10G SFP Transceiver Modules refers to 10G SFP Plus transceivers, It is known that sfp + is an enhanced version of the SFP that supports data rates up to 10 Gbit /s. Several standards 10G SFP has been set free, 10GBASE-SR is for fiber optic multimode OM3, SFP corresponding more distance work 300 meters max, 10GBASE-LR is fiber optic mode only, corresponding SFP more distance work of 10 km , 10GBASE-LRM is forFDDI multimode fiber , the SFP+ supports remote work of 220 meters .

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The Best Video Conferencing App for Android and iPhone | ezTalks

The Best Video Conferencing App for Android and iPhone | ezTalks
Thanks to the development of video conference technology, you can attend or host a conference or meeting anywhere in the world from the comfort of your own iPhone or Android phone. Many video conferencing providers release their own video conferencing apps with all kinds of features, but which one is the best? Therefore, I am going to share a list of top best video conferencing app for Android and iPhone, which might make it more convenient for your teams to host online meeting remotely.

1. Skype
2. Google Hangouts
3. Tango
4. Viber
5. The Best Group Video Conferencing App-ezTalks Cloud Meeting

1. Skype

As one of the most popular video chat apps, Skype has dominated the video chat industry for years with more than 700 million registered users. It supports both private and group video/voice calls on iPhone and Android phone as well as multiple operating systems. The service also offers video chat, video messaging, and instant messaging within a streamlined build, while giving users the option to make VoIP calls to outside numbers for a small fee.

2. Google Hangouts

Google Hangouts is also one of the best video conferencing app for Android and iPhone users. It is simple to use. You can directly sign in the service with your Google or Gmail account with no need to sign up any account. As one of the best video conferencing tools, it supports to make video conference calls with up to 10 participants. You can also call any phone number in the world. All calls to other Google Hangouts users are free.

3. Tango

Tango is one of the best video conferencing app for Android and iPhone. You can use it as an alternative to Skype or Google Hangouts. It supports member-to-member video calls, voice calls, text messaging, and photo sharing. The app lets you engage in group calls of up to 50 people and requires no more than your phone number, email address, and first name to sign up. It also supports to send music messages powered by Spotify.

4. Viber

Just like the former three video conferencing apps, Viber also enables you to chat with your contacts on your Android phone and iPhone as well. It also allows you to share photos, videos, and express yourself with its thousands of amazing stickers. You can also share your location with others or participate in group calls with up to 40 individual users.

5. The Best Group Video Conferencing App-ezTalks Cloud Meeting

The above four apps are more suitable for making person-to-person video calls with your family or friends. If need to make video conferencing for business with your teams, you'd better choose the best group video conferencing app – ezTalks Cloud Meeting.
Generally speaking, most of best video conferencing tools are expensive. However, ezTalks Cloud Meeting delivers a free video conferencing service that enables you to host or join online meetings with up to 100 participants as long as you talk for no more than 40 minutes per time.

Why ezTalks Cloud Meeting Is the Best Video Conferencing App for Groups:

•Free trial supports to make video conference with up to 100 participants;
•It allows live broadcasting via browser;
•Offers full screen and gallery view for a better visual effect;
•Shares interactive whiteboard to brighten your ideas;
•Shares desktop and application during a meeting;
•Shares various kinds of files, like documents, PDFs, PPTs;
•Supports to host meetings instantly or schedule meetings;
•Records meetings and save as video or audio for playback later;
•Supports both private chat and group chat;
•Supports to make presenters;
•Fully compatible with Android phone and iPhone/iPad.

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How to Restore iPhone 7 to Factory Settings

If your iPhone 7 is in problem and you need to factory reset it. In the situation, you want to make sure that all your personal data, apps, photos, music, emails, etc are removed from the device. This can be achieved by Resetting your iPhone 7 to its Factory Default Settings. And the post will show you how to restore iPhone 7 to factory settings.

Method 1. How to Factory Reset iPhone 7 with iTunes

1. Plug iPhone 7 into the computer with the USB cable. The iTunes on your computer will automatically launch. If not, double-click the icon to start it.

2. Click the name of your iPhone 7 at the upper right corner of iTunes, and then the information of your iPhone 7 will be shown. Click the “Restore iPhone” button in the window to start.

3. iTunes will ask whether you want to back up iPhone 7 before restoring. You’d better choose “Yes” for the reset will erase the contents in your iPhone 7. Then iTunes will start restoring your iPhone 7 to factory settings.

4. Click Restore again to confirm. Then iTunes erases your iPhone 7 and installs the latest iOS software. After you restore your iPhone 7 to factory settings, it will restart. Now you can set it up as new.

Method 2. How to Restore iPhone 7 to Factory Settings without iTunes

You will also be able to reset iPhone to factory settings within your iPhone. You just need to go to “Settings > General > Reset” and then choose the categories you want to reset and then apply it. If you choose “Reset All Contents and Settings”, then you will get all the files in your iPhone erased.
Once you tap on “Erase All Content and Settings”, you will be asked to enter your Apple ID password. Next, you will see a Popup Message informing you that All media, data and settings will be erased from your iPhone. Click on Erase iPhone to factory reset iPhone 7.

Method 3. How to Restore iPhone 7 to Factory Settings without Apple ID

If you have no Apple ID or pass code, you can factory reset iPhone 7 without Apple ID. To factory reset iPhone without Apple ID, you need first put iPhone 7 into DFU mode and connect it to your iTunes. Your iTunes will help you to reset your iPhone 7 without entering Apple ID easily. Restoring iPhone 7 to factory settings with this method will result in wiping all the data in your iPhone. The following steps will show you how to do that.
1. Open iTunes on your computer and connect your iPhone 6 Plus to the computer with a USB cable.

2. After that, turn off you device. Press and hold the Home button for 3 seconds.

3. Put your iPhone 6 Plus into DFU mode: Press and hold the Power and Home button for 10 seconds. Then release the power button and keep holding the home button. When you see the Apple logo disappears, you have successfully put your iPhone 6 Plus into DFU mode.

4. When iTunes detects that your iPhone 7 is in recovery mode, you can restore it now.

5. Click on Restore iPhone 6 Plus. Then you will be notified after the reset and your iPhone 6 Plus will take a restart.